tag:theconversation.com,2011:/global/topics/molecules-24416/articlesMolecules – The Conversation2023-09-07T18:00:25Ztag:theconversation.com,2011:article/2130252023-09-07T18:00:25Z2023-09-07T18:00:25ZSeparating molecules is a highly energy-intensive but essential part of drug development, desalination and other industrial processes – improving membranes can help<figure><img src="https://images.theconversation.com/files/546739/original/file-20230906-15-1tywxl.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2121%2C1412&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Molecules are often separated by their size, shape or other properties.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/abstract-spheres-flowing-through-a-circle-shaped-royalty-free-image/1336236614">twomeows/Moment via Getty Images</a></span></figcaption></figure><p>Separating molecules is critical to producing many essential products. For example, in <a href="https://www.britannica.com/technology/petroleum-refining">petroleum refining</a>, the hydrocarbons – chemical compounds composed of hydrogens and carbons – in crude oil are separated into gasoline, diesel and lubricants by sorting them based on their molecular size, shape and weight. In the <a href="https://doi.org/10.1038/s41586-022-05032-1">pharmaceutical industry</a>, the active ingredients in medications are purified by separating drug molecules from the enzymes, solutions and other components used to make them. </p>
<p>These separation processes take a substantial amount of energy, accounting for <a href="https://doi.org/10.1038/532435a">roughly half of U.S. industrial energy use</a>. Traditionally, molecular separations have relied on methods that require intensive heating and cooling that make them very energy inefficient. </p>
<p>We are <a href="https://scholar.google.com/citations?user=wiZJ2yAAAAAJ&hl=en">chemical and</a> <a href="https://scholar.google.com/citations?user=ryUNRywAAAAJ&hl=en">biological engineers</a>. In our newly published research, we designed a new type of <a href="https://www.science.org/doi/10.1126/science.adh2404">membrane with nanopores</a> that can quickly and precisely separate a diverse range of molecules under harsh industrial conditions.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/mxqOPdEUNTs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Membranes are one method to desalinate water.</span></figcaption>
</figure>
<h2>Membrane technology</h2>
<p><a href="https://en.wikipedia.org/wiki/Membrane">Membranes are physical barriers</a> that can separate molecules in a mixture like a sieve based on their size or affinity – such as charge or polarity – to the membrane material. For example, <a href="https://www.genome.gov/genetics-glossary/Cell-Membrane">your cells</a> are surrounded by a membrane that transports nutrients into it and transports toxins out of it. <a href="https://en.wikipedia.org/wiki/Membrane_technology">Membrane technology</a> include synthetic barriers that can separate molecules in industrially important mixtures at a lower energy cost than traditional methods. </p>
<p>Currently available membranes, including those used in large-scale <a href="https://doi.org/10.1126/science.abb8518">seawater desalination</a>, suffer from instability at high temperatures and when exposed to <a href="https://www.cdc.gov/niosh/topics/organsolv/default.html#">organic solvents</a> – carbon-based chemicals that dissolve other substances. This has limited the use of membranes in many industrial separations. </p>
<p><a href="https://doi.org/10.1126/science.aax3103">Inorganic materials</a> are more stable and better able to survive industrial conditions. Previous studies have focused on making inorganic membranes that are ultrathin in order to allow specific molecules to pass through. But thinness increases the likelihood of creating defects and pinholes in the membrane, and would be difficult to make on an industrial scale. </p>
<h2>Improving membrane separation</h2>
<p>We developed a technique to make a new inorganic material called <a href="https://www.science.org/doi/10.1126/science.adh2404">carbon-doped metal oxide</a> that can separate organic molecules smaller than one nanometer (for scale, a <a href="https://www.nano.gov/nanotech-101/what/nano-size">gold atom</a> is a third of a nanometer in diameter).</p>
<p>Taking inspiration from an existing technology that manufacturers use to make semiconductors, called <a href="https://doi.org/10.3762/bjnano.5.123">molecular layer deposition</a>, we worked with two low-cost reactants from that process and generated thin films. These films contain nanopores that can be precisely tuned to control the separation of molecules ranging from 0.6 to 1.2 nanometers in diameter.</p>
<p>One of the key features of our membrane is that it can <a href="https://www.science.org/doi/10.1126/science.adh2404">withstand harsh conditions</a>. These membranes are stable up to 284 degrees Fahrenheit (140 degrees Celsius) and pressures up to 30 atmospheres (around 441 pounds per square inch) in the presence of organic solvents. This stability is critical, as many industrial separation processes can save tremendous amounts of energy when carried out under high temperatures. </p>
<p>As a demonstration, we used our membrane in the molecule separation step during the manufacture of the pesticide boscalid. By tailoring the pore sizes of our membranes to match the sizes of the molecules in the mixture, we were able to <a href="https://www.science.org/doi/10.1126/science.adh2404">separate each individual component</a> of reactant, product and catalyst. Because of the stability of our membrane, we were able to carry out the whole process at 194 F (90 C), the temperature at which the reaction takes place, eliminating the need to reduce the temperature during the separation process. This can significantly reduce energy consumption and, in turn, reduce the carbon footprint of the industrial process. </p>
<p>We believe our membrane can be used in many similar industrial processes, including those involving harsh conditions where traditional membranes would fail, and are confident that it can be quickly scaled up. This can open the door for researchers and manufacturers to use membranes in previously unexplored applications.</p><img src="https://counter.theconversation.com/content/213025/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Miao Yu receives funding from National Science Foundation.</span></em></p><p class="fine-print"><em><span>Bratin Sengupta does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Around half of US industrial energy use goes toward separating molecules in industrial processes. Developing materials that can withstand harsh industrial conditions can help increase efficiency.Bratin Sengupta, Ph.D. Candidate in Chemical and Biological Engineering, University at BuffaloMiao Yu, Professor of Chemical and Biological Engineering, University at BuffaloLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2104282023-08-04T12:29:16Z2023-08-04T12:29:16ZBefore he developed the atomic bomb, J. Robert Oppenheimer’s early work revolutionized the field of quantum chemistry – and his theory is still used today<figure><img src="https://images.theconversation.com/files/541027/original/file-20230803-25-pvmco1.jpg?ixlib=rb-1.1.0&rect=0%2C7%2C2615%2C2031&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">J. Robert Oppenheimer is responsible for a fundamental idea in the field of quantum chemistry. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/87e22879387a45cb8083993acdcbe034?ext=true">AP Photo/John Rooney</a></span></figcaption></figure><p>The release of the film “<a href="https://www.oppenheimermovie.com/">Oppenheimer</a>,” in July 2023, has renewed interest in the enigmatic scientist J. Robert Oppenheimer’s life. While Oppenheimer will always be recognized as the <a href="https://ahf.nuclearmuseum.org/ahf/profile/j-robert-oppenheimer/">father of the atomic bomb</a>, his early contributions to <a href="https://www.livescience.com/33816-quantum-mechanics-explanation.html">quantum mechanics</a> form the bedrock of modern <a href="https://www.sciencedirect.com/topics/chemistry/quantum-chemistry">quantum chemistry</a>. His work still informs how scientists think about the structure of molecules today.</p>
<p>Early on in the film, preeminent scientific figures of the time, including Nobel laureates <a href="https://www.nobelprize.org/prizes/physics/1932/heisenberg/facts/">Werner Heisenberg</a> and <a href="https://www.nobelprize.org/prizes/physics/1939/lawrence/biographical/">Ernest Lawrence</a>, compliment the young Oppenheimer on his groundbreaking work on molecules. As a <a href="https://scholar.google.com/citations?hl=en&pli=1&user=df8z7MQAAAAJ">physical chemist</a>, Oppenheimer’s work on molecular quantum mechanics plays a major role in both my teaching and my research. </p>
<h2>The Born-Oppenheimer approximation</h2>
<p>In 1927, Oppenheimer published a paper called “<a href="https://doi.org/10.1142/9789812795762_0001">On the Quantum Theory of Molecules</a>” with his research adviser <a href="https://www.nobelprize.org/prizes/physics/1954/born/biographical/">Max Born</a>. This paper outlined what is commonly referred to as the Born-Oppenheimer approximation. While the name credits both Oppenheimer and his adviser, most historians recognize that the theory is mostly Oppenheimer’s work.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black-and-white old photo of two men wearing jackets and ties. The one on the right is younger and looking down, in the backround is a blackboard with equations written on it." src="https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=489&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=489&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=489&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=614&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=614&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541044/original/file-20230803-23-t9qc82.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=614&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">J. Robert Oppenheimer, on the right, in 1947, speaking to mathematician Oswald Veblen at the Princeton Institute for Advance Study.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/PrincetonOppenheimer1947/cda75d90e0fe4924be9217d9399b34c0/photo?Query=oppenheimer&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=535&currentItemNo=33&vs=true">AP/Anonymous</a></span>
</figcaption>
</figure>
<p>The Born-Oppenheimer approximation offers a way to simplify the complex problem of describing molecules at the atomic level.</p>
<p>Imagine you want to calculate the optimum molecular structure, chemical bonding patterns and physical properties of a molecule using <a href="https://www.britannica.com/science/quantum-mechanics-physics">quantum mechanics</a>. You would start by defining the position and motion of all the atomic nuclei and electrons and calculating the important charge attractions and repulsions occurring between these particles in the <a href="https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/09%3A_Chemical_Bonding_in_Diatomic_Molecules/9.02%3A_The_H_Prototypical_Species">molecule</a>. </p>
<p>Calculating the properties of molecules gets even more complicated at the quantum level, where particles have wavelike properties and scientists can’t pinpoint their exact position. Instead, particles like electrons must be described by a <a href="https://www.britannica.com/science/wave-function">wave function</a>. A wave function describes the electron’s probability of being in a certain region of space. Determining this wave function and the corresponding energies of the molecule is what is known as solving the <a href="https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Thermodynamics_and_Chemical_Equilibrium_(Ellgen)/18%3A_Quantum_Mechanics_and_Molecular_Energy_Levels/18.04%3A_The_Schrodinger_Equation_for_a_Molecule">molecular Schrödinger equation</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/AR23uxZruhE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Solving the Schrödinger equation lets scientists calculate the properties of a molecule.</span></figcaption>
</figure>
<p>Unfortunately, this equation <a href="https://doi.org/10.1134/S1063779622010038">cannot be solved exactly</a> for even the <a href="https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/09%3A_Chemical_Bonding_in_Diatomic_Molecules/9.02%3A_The_H_Prototypical_Species">simplest possible molecule, H₂⁺</a>, which consists of three particles: two hydrogen nuclei (or protons) and one electron. </p>
<p>Oppenheimer’s approach provided a means to obtain an approximate solution. He observed that atomic nuclei are significantly heavier than electrons, with a single proton being nearly 2,000 times more massive than an electron. This means nuclei move much slower than electrons, so scientists can think of them as stationary objects while solving the Schrödinger equation solely for the electrons. </p>
<p>This method reduces the complexity of the calculation and enables scientists to <a href="https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Book%3A_Quantum_States_of_Atoms_and_Molecules_(Zielinksi_et_al)/10%3A_Theories_of_Electronic_Molecular_Structure/10.01%3A_The_Born-Oppenheimer_Approximation">determine the molecule’s wave function</a> with relative ease. </p>
<p>This approximation may seem like a minor adjustment, but the Born-Oppenheimer approximation goes far beyond just simplifying quantum mechanics calculations on molecules. It actually shapes how chemists view molecules and chemical reactions. </p>
<p>When scientists visualize molecules, we usually think of them as a set of fixed nuclei with shared electrons that move between nuclei.
In chemistry class, students typically build “<a href="https://doi.org/10.1021/ed048p407">ball-and-stick</a>” models consisting of rigid nuclei (balls) sharing electrons through a bonding framework (sticks). These models are a direct consequence of the <a href="https://doi.org/10.1007/s002149900049">Born-Oppenheimer approximation</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Three images, one on the left showing simple chemistry annotation of a hexagonal benzene ring of C for carbon connected to H for hydrogen. The second image shows the same shape, but with spheres to represent the atoms and sticks to represent bonds." src="https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=184&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=184&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=184&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=231&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=231&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540016/original/file-20230728-24473-tdzlqu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=231&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The ball-and-stick model shows nuclei represented by spheres – or balls – with shared electron bonds represented by sticks. This image shows the structure of a benzene molecule.</span>
<span class="attribution"><span class="source">Aaron Harrison</span></span>
</figcaption>
</figure>
<p>The Born-Oppenheimer approximation also influenced how scientists think about chemical reactions. During a chemical reaction, atomic nuclei are not stationary; they rearrange and move. Electron interactions guide the nuclei’s movements by forming an <a href="https://chem.libretexts.org/Courses/University_of_California_Davis/UCD_Chem_107B%3A_Physical_Chemistry_for_Life_Scientists/Chapters/2%3A_Chemical_Kinetics/2.06%3A_Potential_Energy_Surfaces/">energy surface</a>, which the nuclei can move on throughout the reaction. In this way, electrons drive the molecule’s progression through a chemical reaction. Oppenheimer demonstrated that the way electrons behave is the essence of chemistry as a science.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing a graph of a chemical reaction, with a molecule arranged one way at the beginning, and another way at the end." src="https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=381&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=381&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=381&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=478&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=478&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540907/original/file-20230802-25-b7ng1i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=478&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Molecules can change structure during a chemical reaction.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Rxn_coordinate_diagram.JPG">Chem540grp1f08/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Computational quantum chemistry</h2>
<p>In the century since the publication of the Born-Oppenheimer approximation, scientists have vastly improved their ability to calculate the chemical structure and reactivity of molecules.</p>
<p>This field, known as computational quantum chemistry, has grown exponentially with the widespread availability of faster, more powerful high-end computational resources. Currently, chemists use computational quantum chemistry for various applications ranging from discovering novel <a href="https://doi.org/10.1016/j.cplett.2021.138723">pharmaceuticals</a> to designing better <a href="https://doi.org/10.1039/D0TC03709E">photovoltaics</a> before ever trying to produce them in the lab. At the core of much of this field of research is the Born-Oppenheimer approximation. </p>
<p>Despite its many uses, the Born-Oppenheimer approximation <a href="https://elliptigon.com/when-born-oppenheimer-fails/">isn’t perfect</a>. For example, the approximation often breaks down in light-driven chemical reactions, such as in the chemical reaction that <a href="https://doi.org/10.1038/nchem.894">allows animals to see light</a>. Chemists are <a href="https://doi.org/10.1098/rsta.2020.0375">investigating workarounds</a> for these cases. Nevertheless, the application of quantum chemistry made possible by the Born-Oppenheimer approximation will continue to expand and improve. </p>
<p>In the future, a new era of <a href="https://www.scientificamerican.com/article/how-quantum-computing-could-remake-chemistry/">quantum computers</a> could make computational quantum chemistry even more robust by performing faster computations on increasingly large molecular systems.</p><img src="https://counter.theconversation.com/content/210428/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Aaron W. Harrison does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Remember building model molecules with balls and sticks in chemistry class? You have J. Robert Oppenheimer to thank for that, as a quantum chemist explains.Aaron W. Harrison, Assistant Professor of Chemistry, Austin CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1919952022-10-07T12:18:38Z2022-10-07T12:18:38ZNobel Prize: How click chemistry and bioorthogonal chemistry are transforming the pharmaceutical and material industries<figure><img src="https://images.theconversation.com/files/488596/original/file-20221006-12-btim8w.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2190%2C1369&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Click chemistry joins molecules together by reacting an azide with a cyclooctyne.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/human-hands-connect-two-circles-royalty-free-image/1360214925">Boris Zhitkov/Moment via Getty Images</a></span></figcaption></figure><p><em>The <a href="https://www.nobelprize.org/prizes/chemistry/2022/press-release/">2022 Nobel Prize in chemistry</a> was awarded to scientists Carolyn R. Bertozzi, Morten Meldal and K. Barry Sharpless for their development of click chemistry and bioorthogonal chemistry.</em> </p>
<p><em>These techniques have been used in a number of sectors, including <a href="https://www.statnews.com/sponsor/2021/12/22/it-takes-two-the-future-of-click-chemistry-therapeutics/">delivering treatments</a> that can kill cancer cells without perturbing healthy cells as well as sustainably and quickly producing large amounts of polymers to build materials. One click chemistry-based drug is currently undergoing <a href="https://clinicaltrials.gov/ct2/show/NCT04106492">phase 2 clinical trials</a>. Bertozzi is a scientific adviser of the company developing the drug.</em></p>
<p><em>We asked chemistry Ph.D. candidate <a href="https://scholar.google.com/citations?user=HaxobcoAAAAJ&hl=en">Heyang (Peter) Zhang</a> of the <a href="http://lin.chem.buffalo.edu">Lin Lab</a> at the University at Buffalo to talk about how these techniques figure in his own research and how they have transformed his field and other industries.</em></p>
<h2>1. How does click and bioorthogonal chemistry work?</h2>
<p><a href="https://doi.org/10.1038/s43586-021-00028-z">Click chemistry</a>, as the name suggests, is a way of building molecules like snapping Lego blocks together. It takes two molecules to click, so researchers refer to each one as click partners. </p>
<p>K. Barry Sharpless and Morten Meldal independently discovered that <a href="https://ehs.stanford.edu/reference/information-azide-compounds">azide</a>, a high-energy molecule with three nitrogens bonded together, and <a href="https://www.angelo.edu/faculty/kboudrea/molecule_gallery/03_alkynes/00_alkynes.htm">alkyne</a>, a relatively inert and naturally rare molecule with two carbons triple-bonded together, are great click partners in the <a href="https://doi.org/10.1021/cr0783479">presence of a copper catalyst</a>. They found that the copper catalyst can bring the two pieces together in an optimal arrangement that snaps them together. Prior to this technique, researchers did not have a way to quickly and precisely make new molecules under accessible conditions, like using water as a solvent at room temperature.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram of click chemistry reaction" src="https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=162&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=162&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=162&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=204&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=204&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488632/original/file-20221006-26-yu5sd6.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=204&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">By combining an azide with a cyclooctyne, bioorthogonal chemistry allows researchers to join molecules quickly together without disturbing the rest of the cell.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Clickscheme.png">Cliu89/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>Chemical biologists quickly realized that click reactions can be a fantastic way to probe living systems like cells because they produce little to no toxic byproducts and can happen quickly. However, the copper catalyst is itself toxic to living systems.</p>
<p>Carolyn Bertozzi devised a workaround for this issue by <a href="https://doi.org/10.1021/ja044996f">removing the copper catalyst from the reaction</a>. She did this by placing the alkyne into a ring structure, which drives the reaction forward using the ring strain produced from molecules forced into a cyclical shape. These bioorthogonal reactions, or reactions that happen “parallel” to the chemical environment of the cell, can occur in cells without perturbing their normal chemistry.</p>
<h2>2. How do you use this chemistry in your work?</h2>
<p>In <a href="https://youtu.be/-Ch3VJhIbH4">an interview</a>, Carolyn Bertozzi stated that the next steps for bioorthogonal chemistry are to find new reactions and applications for it. Our lab’s research focuses exactly on that. </p>
<p>My colleagues and I apply this technique to track molecules we are interested in as they naturally behave in a cell. In a living cell, we were able to <a href="https://doi.org/10.1021/jacs.8b00126">add a probe to a receptor</a> that plays a role in a number of cellular processes.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/wI7pEqRM3mM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Carolyn Bertozzi is one of the winners of the 2022 Nobel Prize in chemistry.</span></figcaption>
</figure>
<p>To find new reactions, our lab has spent the last 15 years to <a href="https://doi.org/10.1002/cbic.202200175">push how fast bioorthogonal reactions can run</a>. Speed is important because many molecules in living organisms are present in low concentrations, and using too much of the chemicals required for the reaction can be toxic for the cell. The faster the reaction, the fewer the unwanted side reactions.</p>
<p>We pioneered another way to achieve click and bioorthogonal reactions with even faster speed. Instead of using an azide and an alkyne like the Nobel Prize winners did originally, we used two other molecules that join together when a light is shined on them. With this technique, we are able to add molecules to the surface of a live cell in <a href="https://doi.org/10.1021/jacs.1c10354">as little as 15 seconds</a>. We can then observe how a particular structure on a cell functions in its natural environment, or detect how it changes when exposing it to drugs or other substances. Researchers can then more easily test how cells react to potential treatments.</p>
<p>Currently, we are working to develop a new method of triggering these reactions without light. We are actively working on using bioorthogonal chemistry to improve PET imaging to screen and monitor tumors.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Digram depicting " src="https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=442&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=442&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=442&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=555&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=555&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488633/original/file-20221006-12-s0i0ni.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=555&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bioorthogonal chemistry can be used for ‘click-to-release’ cancer drugs.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1038/s41467-018-03880-y">Rossin 2018 (Nature Communications)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>3. Why are these techniques so important to your field?</h2>
<p>Prior to click and bioorthogonal chemistry, there was no way of visualizing molecules in living cells in their natural state.</p>
<p>As an analogy, imagine you needed to find a specific dollar bill with the serial number 01234567. That would be a pretty daunting task. It would require you to go through every dollar you can get your hands on and verify whether the serial number is the one you are looking for. </p>
<p>Tracking molecules in our body is just as hard, if not more. Because biological environments are so complex, it was previously impossible to add a probe to just the molecule of interest without accidentally tagging something else, or worse, altering the normal chemistry of the cell. With bioorthogonal reactions, however, researchers can essentially add a GPS tracker to the molecule without affecting the rest of the cell.</p><img src="https://counter.theconversation.com/content/191995/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Heyang (Peter) Zhang works in Lin's lab at the University at Buffalo.</span></em></p>Click and bioorthogonal chemistry has enabled researchers to closely study how molecules work in their natural state in living organisms, with applications that span from cancer treatment to polymers.Heyang (Peter) Zhang, PhD Candidate in Chemistry, University at BuffaloLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1848922022-07-11T12:30:22Z2022-07-11T12:30:22ZWhat do molecules look like?<figure><img src="https://images.theconversation.com/files/471251/original/file-20220627-20-ydsy5i.jpg?ixlib=rb-1.1.0&rect=2%2C1%2C782%2C774&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A nanographene molecule imaged by noncontact atomic force microscopy.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Hexabenzocoronene_AFM_2.jpg">Patrik Tschudin/gross3HR/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>What do molecules look like? – Justice B., age 6, Wimberley, Texas</strong></p>
</blockquote>
<hr>
<p>A molecule is a group of atoms bonded together. Molecules make up nearly everything around you – your skin, your chair, even your food. </p>
<p>They vary in size, but are extremely small. You can’t see an individual molecule with your eyes or even a microscope. They are 100,000 times smaller than the <a href="https://hypertextbook.com/facts/1999/BrianLey.shtml">width of a hair</a>.</p>
<p>The smallest molecule is made of two atoms stuck together, while a <a href="https://doi.org/10.1126/science.270.5244.1905-a">large molecule</a> can be a combination of 100,000 atoms or more. A molecule can be a repeat of the same atom, such as the oxygen molecules we breathe, or can be made up of a variety of atoms, such as a sugar molecule made of carbon, oxygen and hydrogen. </p>
<p>But what do molecules look like? It all begins with their building blocks: atoms. </p>
<h2>Opposites attract</h2>
<p>The <a href="https://education.jlab.org/atomtour/">particles of matter that make up an atom</a> are not all the same. They can have a positive charge, a negative charge or no charge. Scientists call them protons, electrons and neutrons. </p>
<figure>
<img src="https://cdn.theconversation.com/static_files/files/2147/A%CC%81tomo_de_Oro.gif?1656372844">
<figcaption> <span class="caption">A gold atom has a dense center made of 79 protons and 118 neutrons, with a more-spread-out cloud of 79 electrons around it. Illustration created by Galarza Creador.</span></figcaption>
</figure>
<p>Neutrons with no charge and protons with a positive charge form the heavy center of the atom. The negatively charged electrons surround this small center.</p>
<p>As atoms approach each other to potentially join and make molecules, the negative electrons in one atom are attracted to the positive protons in the other, and vice versa. Both atoms adjust themselves accordingly.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing a round single atom, top. Below are two atoms stretched into oval shapes, with the positive part of one drawn to the negative part of the other." src="https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=270&fit=crop&dpr=1 600w, https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=270&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=270&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=340&fit=crop&dpr=1 754w, https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=340&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/471509/original/file-20220629-17-tyb14b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=340&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When an atom is alone, the negative electrons surrounding its center are symmetric. As two atoms approach, the negative electrons of one atom move toward the positive center of the other atom.</span>
<span class="attribution"><span class="source">Christine Helms</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>You can compare it to trying to choose a seat in a classroom. There are some rules. For example, you have to stay in the classroom and you cannot sit on top of someone. Following those rules, you might try to sit next to your friends and far from your enemies. Finding the perfect position so everyone in the class is happy is similar to finding the perfect position for the atoms in a molecule. Sometimes, atoms cannot find a happy arrangement and no molecule is formed.</p>
<h2>Seeing the unseeable</h2>
<p>If molecules are too small to see with your eyes or even a powerful microscope, how do scientists see them? The answer is they have developed special tools to do it.</p>
<p>One tool uses X-rays, which you might know about since doctors use them to see bones in the body. <a href="https://theconversation.com/curious-kids-how-do-x-rays-see-inside-you-85895">X-rays are a type of light that human eyes can’t see</a>, <a href="https://www.amnh.org/research/natural-science-collections-conservation/general-conservation/preventive-conservation/light-ultraviolet-and-infrared">like ultraviolet or infrared light</a>. </p>
<p>When scientists <a href="https://www.sciencemuseum.org.uk/objects-and-stories/chemistry/x-ray-crystallography-revealing-our-molecular-world">shoot X-rays at molecules</a>, some bounce off. Scientists can record these rebounding X-rays and use their patterns to figure out what individual molecules look like. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A scattering of black dots on a white background." src="https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/471249/original/file-20220627-22-lv4r5v.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">X-rays that bounce off the atoms in a protein molecule form the black dots in the above image. The location of these dots tells scientists how the atoms are arranged in the molecule.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Lysozym_diffraction.png">Del45/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>In 1912, one of the <a href="https://doi.org/10.1038/491186a">first molecules seen this way was salt</a> (NaCl) – the molecule that makes up the ingredient we all know and love on french fries.</p>
<p>Scientists have invented other methods to see molecules, too. Similar to how the electrons change their behavior as two atoms come close together, the center of the atom can also change its behavior. A technique called <a href="https://www.jeol.co.jp/en/products/nmr/basics.html">nuclear magnetic resonance</a> detects those changes to the center of the atom and uses them as clues to determine what atoms are close by. </p>
<p>An <a href="https://www.parksystems.com/medias/nano-academy/how-afm-works">atomic force microscope</a> works like a flimsy diving board that shakes when you walk and jump on it. But this diving board is extremely small, so small that a negative charge on the end of it will bend it toward the positive center of an atom. Moving this diving board around and watching how it bends can show the location of atoms in a molecule.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/8gCf1sEn0UU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">An animation showing how an atomic force microscope works.</span></figcaption>
</figure>
<p>One more technique scientists have developed to see molecules is called <a href="https://cryoem.slac.stanford.edu/what-is-cryo-em">cyro-electron microscopy</a>. First, scientists freeze molecules to a temperature much colder than snow or ice. Then they shoot electrons at the molecule and collect those that pass through to make an image. <a href="https://theconversation.com/chilled-proteins-and-3-d-images-the-cryo-electron-microscopy-technology-that-just-won-a-nobel-prize-85229">This technique won</a> the <a href="https://www.nobelprize.org/prizes/chemistry/2017/press-release/">Nobel Prize in Chemistry in 2017</a>. </p>
<h2>All shapes and sizes</h2>
<p>So what do molecules look like? They are a grouping of atoms, with the center containing most of the material, while the rest is largely empty space. Each atom has a specific position where it is happy, much like the students in that classroom. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Side by side diagram of a flat molecule and a round molecule." src="https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=315&fit=crop&dpr=1 600w, https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=315&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=315&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=396&fit=crop&dpr=1 754w, https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=396&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/471674/original/file-20220629-21-45b5zt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=396&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Diagrams of the atoms making up the molecules benzene, left, and fullerene, right.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Buckminsterfullerene-perspective-3D-balls.png">Jynto (left) Benjah-bmm27 (right)/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>Every molecule is different – some are really different. For example, benzene is flat like a pancake, while fullerene is round like a ball. <a href="http://www.chemspider.com/Chemical-Structure.10338857.html">Penguinone</a> can be drawn to look like a penguin, while other molecules appear to look completely random. But the positions of atoms in a molecule are never random. </p>
<p>While scientists know what a lot of molecules look like, there are some we’re still trying to figure out. Knowing these answers can lead to inventions of new materials and <a href="https://www.mdpi.com/1422-0067/20/11/2783/htm">medicines</a>. </p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/184892/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Helms does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A physicist explains how atoms arrange themselves into molecules – and how scientists are able to image these tiny bits of matter that make up everything around you.Christine Helms, Associate Professor of Physics, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1833662022-06-13T13:29:32Z2022-06-13T13:29:32ZMolecular research could help Nigeria solve a host of health problems<figure><img src="https://images.theconversation.com/files/464752/original/file-20220523-42302-ho3i3z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Molecular research like that conducted at the African Centre of Excellence for Genomics of Infectious Diseases in Nigeria is key to medical breakthroughs.</span> <span class="attribution"><span class="source">PIUS UTOMI EKPEI/AFP via Getty Images</span></span></figcaption></figure><p>Our world and everything in it is made up of innumerable tiny molecules. These molecules are the smallest units of chemical compounds or living things. Viruses, bacteria, parasites, plants, animals, humans: each organism is underpinned by molecules. Studying them allows scientists to understand the basic principles and interactions that govern all forms of life. </p>
<p>Shifts at such basic levels change the way an organism looks or functions. That’s critical in understanding diseases, for one thing. During the COVID-19 pandemic, molecular research enabled scientists to quickly understand how the new coronavirus behaved and how to prevent infection. That, in turn, drove <a href="https://www.scienceboard.net/index.aspx?sec=rca&sub=ASGC_2022&pag=dis&ItemID=4298">vaccine development</a>.</p>
<p>Molecular research could also, in future, make it possible to personalise medicine – basing treatment on a patient’s DNA. And it may be key to progress in the treatment of diseases such as sickle cell anaemia, diabetes and cancer.</p>
<p>There’s a problem, though: molecular research is expensive. It requires specialised equipment and chemicals, which is costly.</p>
<p>In Nigeria, where I conduct molecular research – and in many other African countries – there is very little state funding for research and development. Nigeria’s <a href="https://tetfundserver.com/">TETFund</a>, the government agency responsible for all higher education funding, has very <a href="https://www.premiumtimesng.com/news/top-news/399432-buhari-approves-n7-5-billion-for-research-grants.html">limited resources</a>. Molecular research is often neglected in funding decisions in favour of other forms of research that could provide immediate solutions to pressing societal needs, such as immediate control measures for disease outbreaks.</p>
<p>As I argued in a recent <a href="https://www.frontiersin.org/articles/10.3389/frma.2021.788673/full">journal article</a>, though, molecular research can help address some of Nigeria’s health needs. Nigeria has a rich <a href="https://medcraveonline.com/IJAWB/factors-affecting-the-population-trend-of-biodiversity-in-the-niger-delta-region-of-nigeria.html">biodiversity</a> of humans, animals and plants whose molecular compositions may hold clues to future advancements in medical science. The country also bears a huge <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)02722-7/fulltext">burden</a> of infectious disease. Microorganisms that cause <a href="https://www.globalcitizen.org/en/content/nigeria-neglected-tropical-diseases-explainer/">diseases</a> abound in the tropical climate of Nigeria. </p>
<p>Investment in research into the molecular characteristics of these microorganisms would go a long way in disease control and management both locally and globally. </p>
<h2>Untapped contributions</h2>
<p>It’s worth noting what Nigeria’s molecular research scientists have already been able to achieve without good resources. </p>
<p>They were at the forefront of sequencing the SARS-CoV-2 genome within days of the first infection being recorded on Nigerian soil. This work allowed them to publish the <a href="https://virological.org/t/first-african-sars-cov-2-genome-sequence-from-nigerian-covid-19-case/421">first SARS-CoV-2 sequence data</a> on the African continent. This was made possible by many years of international and local funding to build capacity at the African Centre of Excellence for the Genomics of Infectious Disease and the Nigerian Institute of Medical Research.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/nigerian-scientists-have-identified-seven-lineages-of-sars-cov-2-why-it-matters-144234">Nigerian scientists have identified seven lineages of SARS-CoV-2: why it matters</a>
</strong>
</em>
</p>
<hr>
<p>Imagine how much more could be done and how Nigeria could contribute to global health solutions if its numerous excellent scientists were properly equipped with adequate facilities. </p>
<p>South Africa has demonstrated this dedicated research support via its <a href="https://www.nrf.ac.za/">National Research Foundation</a>. Huge funds have been invested in research for the control of HIV and AIDS and, more recently, COVID-19.</p>
<p>At present, most Nigerian molecular research scientists do not have the specialised research equipment they need. This is because of cost and limited availability. Most of this equipment, and the chemical reagents needed for this work, is imported. There are a few specialised reference molecular laboratories in the country, but not nearly enough to serve the needs of this nation of more than <a href="https://data.worldbank.org/indicator/SP.POP.TOTL?locations=NG">200 million people</a>. </p>
<p>Universities, which are the ideal spaces for such research facilities, don’t offer adequate institutional support for procuring molecular research equipment and reagents. </p>
<p>Yet there are many diseases peculiar to the country and region, for which new treatments could be easily developed with the aid of molecular research. They include genetic diseases like <a href="https://www.afro.who.int/health-topics/sickle-cell-disease">sickle cell</a>, noncommunicable diseases like <a href="https://diabetesatlas.org/data/en/country/145/ng.html">diabetes</a>, and infectious diseases like <a href="https://theconversation.com/africa/topics/malaria-762">malaria</a> and <a href="https://www.who.int/health-topics/neglected-tropical-diseases#tab=tab_1">neglected tropical diseases</a> (among them river blindness and sleeping sickness or African trypanosomiasis). </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/new-finding-offers-breakthrough-in-beating-african-sleeping-sickness-65569">New finding offers breakthrough in beating African sleeping sickness</a>
</strong>
</em>
</p>
<hr>
<p>Nigeria – and the African continent – cannot continue to wait for western researchers to find solutions to these peculiar health challenges. </p>
<h2>Concerted effort</h2>
<p>Nigeria has the opportunity to contribute an enormous amount of knowledge to molecular research. For this to happen, a concerted effort is required by the government, institutions, local and international funding bodies, and molecular researchers themselves. </p>
<p>COVID-19 has taught us that a health problem in one place could threaten global health. Therefore all hands should be on deck to tackle health challenges wherever they occur. </p>
<p>There is a strong need for national and international funding bodies to increase funding allocations to improve molecular research capacity in Africa. Also, universities and research institutions should provide an enabling environment by providing easy access to the equipment and facilities that researchers need. Researchers will thus be encouraged to find solutions to health challenges and train more scientists.</p><img src="https://counter.theconversation.com/content/183366/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chinwe Uzoma Chukwudi receives funding from National Institutes of Health, Bill and Melinda Gates Foundation and African Academy of Sciences. </span></em></p>Molecular research is expensive, but worth it because of the burden of disease that it could relieve.Chinwe Uzoma Chukwudi, Senior lecturer in Molecular Pathology and Microbial Genetics, University of NigeriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1824862022-05-09T16:46:08Z2022-05-09T16:46:08ZUnlocking the secrets of maple syrup, one molecule at a time<figure><img src="https://images.theconversation.com/files/461824/original/file-20220506-18-5xkyt0.jpg?ixlib=rb-1.1.0&rect=42%2C67%2C5565%2C3665&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Maple syrup contains bioactive molecules whose benefits go far beyond the simple pleasure of a sweet treat.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Nature conceals a phenomenal number of molecules as varied as they are imperceptible. The plant kingdom is particularly chemically complex. </p>
<p>Plant evolution has taken place over hundreds of millions of years, giving plants the ability to respond to various environmental stresses and threats. Several species have developed an arsenal of molecules allowing them to adapt and to protect themselves against competitors and predators. Some of these molecules also have health benefits for the animals that consume them.</p>
<p>Advances in food science over recent decades show that many plants provide a wealth of benefits that, until recently, were largely unknown. Taken together, these discoveries support more than ever the fact that a varied and balanced diet offers benefits that go beyond simple energy intake. As a result, consumer demand for plant-based foods with higher nutritional value is currently at record highs. This trend has yet to run out of steam. At the same time, sugary foods are increasingly marginalized and categorized as unhealthy. </p>
<p>But in the realm of sweets, maple syrup is finally claiming its rightful place! Maple syrup is no longer only the jewel of Canada’s culinary heritage, its nutritional reputation is also improving. Because of its unique natural source and manufacturing process, maple syrup contains bioactive molecules whose benefits go far beyond the simple pleasure of a sweet treat.</p>
<h2>Benefits that go beyond energy intake</h2>
<p>In eastern Canada, March and April herald maple sugaring time. Higher temperatures cause <a href="https://doi.org/10.1139/b03-079">maple trees to convert their energy reserves (stored as complex carbohydrates) into soluble sugars</a> that mix with the water in the tree. Producers collect the flavoured sap by drilling holes in the trees.</p>
<figure class="align-center ">
<img alt="Maple syrop in a bottle on a wooden table." src="https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=461&fit=crop&dpr=1 600w, https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=461&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=461&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=580&fit=crop&dpr=1 754w, https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=580&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/459344/original/file-20220422-18-zenfms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=580&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Maple syrup, Canada’s liquid gold, contains bioactive molecules whose benefits go far beyond the simple pleasure of sweet treats.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>The sap is approximately 98 per cent water, and it takes about 40 litres of this maple water to generate one litre of syrup. During this concentration process, the levels of sugars and nutrients increase substantially. The high temperature that comes from boiling the sap causes a series of chemical reactions as the excess water evaporates.</p>
<p>The main components of maple syrup are sucrose and water. Glucose and fructose also contribute to the sweet taste of the syrup, but to a lesser extent. While these three simple carbohydrates are sources of energy, maple syrup is also an excellent source of manganese and riboflavin (vitamin B2), as well as a significant source of other <a href="http://www.internationalmaplesyrupinstitute.com/uploads/7/0/9/2/7092109/__nutrition_and_health_benefits_of_pure_maple_syrup.pdf">vitamins and minerals (zinc, potassium, calcium and magnesium)</a>.</p>
<p>The composition of phenolic compounds of maple syrup is even more impressive. Since the beginning of the 20th century, <a href="https://doi.org/10.1016/j.foodchem.2021.131817">researchers have discovered more than 100 of these molecules in plants</a>. Many of them are antioxidants, and contribute to the taste, aroma, colour of maple syrup. They are primarily responsible for its recent superfood status. </p>
<p>One of the most promising phenolic components (in terms of biological activities) is a molecule found nowhere other than in Canada’s most famous product.</p>
<h2>A molecule worthy of national pride</h2>
<p>Quebecol – named after the province where <a href="https://www.worldatlas.com/articles/the-world-s-top-producers-of-maple-syrup.html">the majority of the world’s maple syrup production originates</a> – is a polyphenolic compound (carrying several phenol groups), <a href="https://doi.org/10.1016/j.jff.2011.02.004">first isolated in 2011 by a team led by Navindra Seeram at the University of Rhode Island</a>. This compound is so exclusive to maple syrup that it is not even present in raw maple sap! Rather, current knowledge suggests that it is the product of chemical reactions that occur during the transformation of sap into syrup.</p>
<figure class="align-center ">
<img alt="Molecular structure of quebecol" src="https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=434&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=434&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=434&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=546&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=546&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461819/original/file-20220506-22-8urv2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=546&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Structure of quebecol [2,2,3-tris(4-hydroxy-2-methoxyphenyl)propan-1-ol], a molecule exclusively found in maple syrup whose secrets are just beginning to be revealed.</span>
<span class="attribution"><span class="source">(Sébastien Cardinal)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Early laboratory studies, <a href="https://patents.google.com/patent/WO2012167364A1/en">quebecol inhibited cell proliferation of breast cancer and colon cancer cells</a>. But only a small quantity of polyphenol could be isolated, and these tests didn’t go beyond the preliminary stage. More than 20 litres of maple syrup is needed to isolate less than a milligram of quebecol.</p>
<p>Judging that this syrup would be of better use in kitchens than in laboratories, Normand Voyer, a chemistry professor at Laval University, and I (Sébastien) decided to tackle this supply problem. When I was a PhD candidate in 2013, <a href="https://doi.org/10.1016/j.tetlet.2013.07.048">we published a chemical synthesis pathway to build this natural molecule much more efficiently in the laboratory from simple precursors</a>. As this work made quebecol much more accessible, the investigation of its properties continued and deepened.</p>
<p>In particular, Normand Voyer, Daniel Grenier and their teams, in the faculty of dentistry of Laval University, published two studies <a href="https://doi.org/10.1016/j.bmc.2017.01.050">demonstrating the molecule’s anti-inflammatory properties</a>. This research also made it possible to <a href="https://doi.org/10.1016/j.bmcl.2015.11.096">determine the active portion of the molecular structure</a>.</p>
<h2>A compound still relevant today</h2>
<p>Our 2021 study showed that quebecol’s <a href="https://doi.org/10.1021/acsomega.1c03312">anti-inflammatory properties may benefit periodontal disease</a>, a severe infection of the gums. We expect additional studies to be published this year, including one showing that quebecol might help with the treatment of a skin condition.</p>
<p>Although the evidence of biological activity of quebecol has been limited to in vitro experiments, these results certainly encourage further study in more complex systems. It is also important to note that the results came from using the isolated pure molecule. </p>
<p>These studies do not propose using pure maple syrup as a medicinal agent against different conditions. Given the quantity of maple syrup one would have to eat to get the necessary dose of quebecol, the harms from a massive ingestion of sugar would obscure any benefit. It’s also difficult to establish the distribution of the molecule in the human body when it’s taken orally.</p>
<p>In any case, these discoveries once again highlight the uniqueness of maple syrup and help to strengthen its status as a singular food. Perhaps it contains other equally promising molecules just waiting to be discovered. Let’s bet that this local treasure has not yet revealed all its secrets!</p><img src="https://counter.theconversation.com/content/182486/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Les auteurs ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'ont déclaré aucune autre affiliation que leur organisme de recherche.</span></em></p>Apart from being a jewel of Canada’s culinary heritage, maple syrup has a complex chemical constitution.Sébastien Cardinal, Professeur en chimie organique, Université du Québec à Rimouski (UQAR)Amy McMackin, Candidate MSc Chimie, Université du Québec à Rimouski (UQAR)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1623332021-06-21T12:20:40Z2021-06-21T12:20:40ZDoes outer space end – or go on forever?<figure><img src="https://images.theconversation.com/files/405990/original/file-20210611-13-pcdwbd.jpg?ixlib=rb-1.1.0&rect=321%2C214%2C5770%2C4271&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">It can stretch your mind to ponder what's really out there.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/silhouette-man-sitting-on-rock-against-royalty-free-image/615314285">Stijn Dijkstra/EyeEm via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>What is beyond outer space? – Siah, age 11, Fremont, California</strong></p>
</blockquote>
<hr>
<p>Right above you is the sky – or as scientists would call it, the atmosphere. It extends about <a href="https://www.nationalgeographic.org/encyclopedia/atmosphere/">20 miles (32 kilometers) above the Earth</a>. Floating around the atmosphere is a <a href="https://kids.britannica.com/kids/article/molecule/353479">mixture of molecules</a> – tiny bits of air so small you take in billions of them every time you breathe.</p>
<p>Above the atmosphere is space. It’s called that because it has far fewer molecules, with lots of empty space between them. </p>
<p>Have you ever wondered what it would be like to travel to outer space – and then keep going? What would you find? <a href="https://ui.adsabs.harvard.edu/search/q=%20author%3A%22singal%2C%20jack%22&sort=date%20desc%2C%20bibcode%20desc&p_=0">Scientists like me</a> are able to explain a lot of what you’d see. But there are some things we don’t know yet, like whether space just goes on forever. </p>
<h2>Planets, stars and galaxies</h2>
<p>At the beginning of your trip through space, you might recognize some of the sights. The <a href="https://www.solarsystemscope.com/">Earth is part of a group of planets</a> that all orbit the Sun – with some orbiting asteroids and comets mixed in, too.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram of the solar system, showing the sun and its orbiting planets." src="https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/405719/original/file-20210610-15-1eygla0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A familiar neighborhood.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/solar-system-artwork-royalty-free-image/529831132">Mark Garlick/Science Photo Library via Getty Images</a></span>
</figcaption>
</figure>
<p>You might know that the Sun is actually just an average star, and looks bigger and brighter than the other stars <a href="https://apod.nasa.gov/apod/ap011018.html">only because it is closer</a>. To get to the next nearest star, you would have to travel through trillions of miles of space. If you could ride on the fastest space probe NASA has ever made, it would still take you thousands of years to get there. </p>
<p>If stars are like houses, then galaxies are like cities full of houses. Scientists estimate there are <a href="https://en.wikipedia.org/wiki/Milky_Way">100 billion stars in Earth’s galaxy</a>. If you could zoom out, way beyond Earth’s galaxy, those 100 billion stars would blend together – the way lights of city buildings do when viewed from an airplane. </p>
<p>Recently astronomers have learned that <a href="https://exoplanets.nasa.gov/">many or even most stars have their own orbiting planets</a>. Some are even like Earth, so it’s possible they might be home to other beings also wondering what’s out there. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An image showing detail of one galaxy, but visually implying there are many more." src="https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=579&fit=crop&dpr=1 600w, https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=579&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=579&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=727&fit=crop&dpr=1 754w, https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=727&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/405722/original/file-20210610-10377-8e930k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=727&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A galaxy among many other galaxies.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/messier-106-a-spiral-galaxy-in-the-constellation-royalty-free-image/495835787">Michael Miller/Stocktrek Images via Getty Images</a></span>
</figcaption>
</figure>
<p>You would have to travel through <a href="https://imagine.gsfc.nasa.gov/features/cosmic/local_group_info.html">millions of trillions more miles of space just to reach another galaxy</a>. Most of that space is almost completely empty, with only some stray molecules and tiny mysterious <a href="https://home.cern/science/physics/dark-matter">invisible particles scientists call “dark matter</a>.”</p>
<p>Using big telescopes, <a href="https://hubblesite.org/contents/articles/hubble-deep-fields">astronomers see millions of galaxies</a> out there – and they just keep going, in every direction. </p>
<p>If you could watch for long enough, over millions of years, it would look like new <a href="https://astronomy.swin.edu.au/cosmos/H/Hubble+Flow">space is gradually being added between all the galaxies</a>. You can visualize this by imagining tiny dots on a deflated balloon and then thinking about blowing it up. The dots would keep moving farther apart, just like the galaxies are.</p>
<h2>Is there an end?</h2>
<p>If you could keep going out, as far as you wanted, would you just keep passing by galaxies forever? Are there an infinite number of galaxies in every direction? Or does the whole thing eventually end? And if it does end, what does it end with? </p>
<p>These are questions scientists don’t have definite answers to yet. Many think it’s likely you would just <a href="https://doi.org/10.1103/PhysRevD.64.043511">keep passing galaxies in every direction, forever</a>. In that case, the universe would be infinite, with no end.</p>
<p>Some scientists think it’s possible the <a href="https://www.quantamagazine.org/what-shape-is-the-universe-closed-or-flat-20191104/">universe might eventually wrap back around on itself</a> – so if you could just keep going out, you would someday come back around to where you started, from the other direction.</p>
<p>One way to think about this is to picture a globe, and imagine that you are a creature that can move only on the surface. If you start walking any direction, east for example, and just keep going, eventually you would come back to where you began. If this were the case for the universe, it would mean it is not infinitely big – although it would still be bigger than you can imagine.</p>
<p>In either case, you could never get to the end of the universe or space. Scientists now consider it unlikely the universe has an end – a region where the galaxies stop or where there would be a barrier of some kind marking the end of space. </p>
<p>But nobody knows for sure. How to answer this question will need to be figured out by a future scientist.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p>
<hr>
<p><em>This article has been updated to correct the distances to the nearest star and galaxy.</em></p><img src="https://counter.theconversation.com/content/162333/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jack Singal does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Astronomers know a lot about what’s in outer space – and think it’s possible it never ends.Jack Singal, Associate Professor of Physics, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1512782021-01-06T19:04:43Z2021-01-06T19:04:43ZCurious Kids: how does the Sun make such pretty colours at sunsets and sunrises?<figure><img src="https://images.theconversation.com/files/372423/original/file-20201202-13-8wbwpd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Light from our setting sun reflecting off storm clouds can give off a some vivid shades of pinks, purples and oranges.</span> <span class="attribution"><span class="source">Jake Clark</span>, <span class="license">Author provided</span></span></figcaption></figure><blockquote>
<p><strong>How does the Sun make such pretty colours at sunsets and sunrises? — Aisling, age 7, Mount Gambier, South Australia</strong></p>
</blockquote>
<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
<p>Hi Aisling. Thank you for this super interesting question! </p>
<p>We love watching all the pretty colours of sunsets and sunrises. But why does this happen, when most of the time the sky is just blue?</p>
<p>Well, it’s all because of light and the fact that light has colour. Believe it or not, the light around you is a combination of all the colours in the world. </p>
<p>But if this is true, why do we only see some colours in the sky at certain times, and not all of them? </p>
<p>To know this, we first need to know how day turns into night.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372776/original/file-20201203-23-heriyu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">In Australia, we get beautiful views of the sun setting on most days — as long as we have a good spot to watch from. The sky lights up with bright reds and oranges.</span>
<span class="attribution"><span class="source">Jake Clark</span></span>
</figcaption>
</figure>
<h2>Earth goes dancing through space</h2>
<p>Our planet, Earth, moves in space with seven other planets nearby. They all spin in circles on the spot, but also move in much larger circles around the Sun. </p>
<p>When the Sun is setting in Australia, this means our side of the planet is turning away from the Sun. During sunrise, we’re turning towards it.</p>
<p>Night time happens when we’re no longer facing the Sun at all. Daytime happens when we have twirled to <a href="https://youtu.be/l64YwNl1wr0">face the Sun</a> directly — so its sunbeams travel (very fast) directly to us. </p>
<p>Although you can’t tell by looking at them, beams of light from the Sun come in different sizes. Scientists measure these sizes using something called “wavelength”. </p>
<p>Each different wavelength of light has its own unique colour. </p>
<h2>Earth is wrapped in its atmosphere</h2>
<p>So we know why the sky is bright during the day and dark at night. And we know sunbeams come in different sizes, or “wavelengths”. </p>
<p>But how does it become the gorgeous colours we see during sunset and sunrise?</p>
<p>This happens because of an important blanket of air wrapped around Earth, called the atmosphere. </p>
<p>Earth’s atmosphere is made up of many very tiny objects called molecules. In fact, all things are made of molecules, including you and me. </p>
<p>But each molecule is much, much smaller than a grain of sand. They’re so small you can’t see them without a microscope — you can only see the bigger things they make.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372778/original/file-20201203-17-19n1dhb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">If you were an astronaut onboard the International Space Station, you’d have crossed Earth’s atmosphere to get there.</span>
<span class="attribution"><span class="source">NASA</span></span>
</figcaption>
</figure>
<h2>How the atmosphere plays with light</h2>
<p>When the Sun’s beams reach Earth, they meet the molecules in Earth’s atmosphere. The molecules then begin to play with the light — bouncing it back and forth between themselves. This is called “scattering”.</p>
<p>The longer a wavelength of light is, the longer it can keep scattering between the molecules in our Earth’s atmosphere before “tiring out” and going back into space. </p>
<p>Blue light has a shorter wavelength than red or pink light. This means it can only bounce between the molecules for a shorter distance.</p>
<p>When Australia is directly facing the Sun (daytime), there’s less atmosphere for the light to pass through. Blue light can easily come out the other side — giving us a <a href="https://www.exploratorium.edu/snacks/blue-sky">blue sky</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Picture of Sydney Harbour Bridge, Australia." src="https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=387&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=387&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=387&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=486&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=486&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372960/original/file-20201204-19-1uaccj5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=486&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Although the sky and ocean are both blue, the reasons for why they’re blue are different.</span>
<span class="attribution"><span class="source">Jake Clark</span></span>
</figcaption>
</figure>
<h2>The colours of sunrise and sunset</h2>
<p>We already know Earth spins in its place. Remember that during sunset in Australia, we are circling away from the Sun and no longer facing it directly.</p>
<p>This means sunlight has to travel through a thicker slice of the atmosphere to reach us. This happens during sunrise too, when Australia is moving towards the Sun. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A digram showing light hitting Australia at two different times of the day." src="https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/377324/original/file-20210106-15-qztr4o.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Here we can see how, to reach Australia, light has to travel through Earth’s atmosphere for a longer distance during sunrise and sunset, when we’re not directly facing the Sun.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>With this larger distance of atmosphere to cover, the blue light gets tired. It can’t keep up anymore, so it mostly bounces back out into space.</p>
<p>But the red, orange and yellow light have longer wavelengths. This means they can scatter for longer and travel through the atmosphere to reach us.</p>
<p>And this is why we have beautiful bright sunsets and sunrises.</p><img src="https://counter.theconversation.com/content/151278/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jake Clark is supported by an Australian Government Research Training Program (RTP) Scholarship.</span></em></p><p class="fine-print"><em><span>Nataliea Lowson is supported by an Australian Government Research Training Program (RTP) Scholarship.</span></em></p>It’s all to do with the light from the Sun and a blanket of air wrapped around Earth called the ‘atmosphere’.Jake Clark, PhD Candidate, University of Southern QueenslandNataliea Lowson, PhD Candidate, University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1475782020-11-11T19:19:33Z2020-11-11T19:19:33ZCurious Kids: Do worms have blood? And if so, what colour is it?<figure><img src="https://images.theconversation.com/files/368765/original/file-20201111-13-x5fk9i.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5742%2C3785&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock </span></span></figcaption></figure><blockquote>
<p><strong>Do worms have blood, and if they do, what colour is it? Momo Bice, aged 9, Carlton</strong></p>
</blockquote>
<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
<p>Hi Momo. Well, the short answer to your question is: yes. Many worms do have blood, and it is either colourless or pink, or red, or even green! But to answer your question properly, first we need to decide what type of worm we are talking about. </p>
<p>There are lots of different sorts of worms. Generally, a worm is any long, thin animal that does not have a backbone, but scientifically we recognise three types of worms: flatworms, roundworms and segmented worms. Worms live in the sea, in sand and soil. Some live inside plants or animals, and we call them parasites.</p>
<p>So let’s look at what blood you might find inside these different types of worms. </p>
<figure class="align-center ">
<img alt="Segmented worm" src="https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368787/original/file-20201111-15-1jhwpuu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Worms live in sea, sand soil, or – if we’re unlucky – even inside us.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>The three worm types</h2>
<p><strong>Flatworms:</strong> These include tapeworms, which are parasites (meaning they live on a host organism), and planaria, which live in ponds and lakes. These animals are so flat they don’t even need blood. They absorb oxygen through their skin and it spreads directly to every cell in their body. As a result they are pretty much colourless, or whitish.</p>
<p><strong>Roundworms:</strong> Also called nematodes, these worms are mainly found in soil. Roundworms can also live as parasites in humans, causing really <a href="https://theconversation.com/with-fewer-resources-were-finding-clever-ways-to-map-river-blindness-in-africa-32126">nasty</a> <a href="https://www.cdc.gov/parasites/toxocariasis/gen_info/faqs.htm">effects</a> such as blindness and brain defects. One large roundworm that lives in the intestines of humans can grow to more than <a href="https://www.cdc.gov/parasites/ascariasis/biology.html">35 centimetres</a> – that’s longer than a standard ruler!</p>
<p>As the name suggests, roundworms are tube-shaped. Their body cavity contains fluid that delivers oxygen to its organs. But this fluid is not called blood, because it does not circulate around the body.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-are-parasites-and-how-do-they-make-us-sick-121489">What are parasites and how do they make us sick?</a>
</strong>
</em>
</p>
<hr>
<p>Most roundworm species are very small, and so can diffuse oxygen through their skin to all parts of their body. But very large roundworms can’t do this as easily, especially when they live inside animals where there is not much oxygen. These large worms use an oxygen-carrying molecule called haemoglobin – more on that in a minute.</p>
<p><strong>Segmented worms:</strong> These worms include earthworms, leeches and marine worms. Also known as annelids, the bodies of segmented worms are divided by grooves into a series of segments. Most have circulatory systems – that is, blood vessels and a heart that pumps blood around the body. </p>
<figure class="align-center ">
<img alt="A flatworm" src="https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368777/original/file-20201111-19-u1jv20.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Flatworms have no body cavity.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>So what colour is the blood?</h2>
<p>The <a href="https://biomolecules101.wordpress.com/2020/01/17/oxygen-transport-proteins-the-colors-of-blood/">colour of blood</a> in any animal is determined by the molecule that carries oxygen and other gases in and out of the body. If the molecule uses iron to carry the oxygen, then the blood is usually red. If it uses copper, the blood is usually blue. But these molecules can also be green and pink. </p>
<p>All these colours except blue are found in worms. Haemoglobin is the most common oxygen-carrying molecule, including in worms. Haemoglobin contains iron, which means most worm blood – including that of earthworms and leeches – is red. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-why-do-leeches-suck-our-blood-117316">Curious Kids: why do leeches suck our blood?</a>
</strong>
</em>
</p>
<hr>
<p>Some segmented worms use a different oxygen-carrying molecule called <a href="https://doi.org/10.1098/rspb.1926.0008">chlorocruorin</a>. The blood of these worms can be either green or red.</p>
<p>One group of segmented marine worms has pink blood. This is because the molecule that carries the oxygen is a type of blood pigment, known as <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/hemerythrin">hemerythrin</a>, which is described as pink or purple.</p>
<p>A few species of segmented worms don’t have any oxygen-carrying molecules at all, so their blood is colourless.</p>
<p>So, the answer to your question is that all segmented worms have blood, while roundworms and flatworms do not. The blood colour depends on the molecule that carries oxygen in that worm. And most worms have red blood, just like us! </p>
<figure class="align-center ">
<img alt="Child's hands holding worms and soil" src="https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/368776/original/file-20201111-21-1c1giiu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">There are three worm types, and not all have blood.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/147578/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Sandeman does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Pink blood, green blood, or no blood at all – when it comes to what’s inside a worm’s body, the answer is more complicated – and fascinating – than you’d think.Mark Sandeman, Honorary Professor, Federation University AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1328272020-06-22T12:16:50Z2020-06-22T12:16:50ZWhat is the slowest thing on Earth?<figure><img src="https://images.theconversation.com/files/342474/original/file-20200617-94049-47hnes.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Lasers create colorful light shows at concerts, are used by doctors in surgeries – and are used in scientific laboratories.</span> <span class="attribution"><span class="source">EyeWolf/Getty Images</span></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>What is the slowest thing on Earth? – Jiwon, Brookline, Massachusetts</strong></p>
</blockquote>
<hr>
<p>In the words of the infamous villain, <a href="https://www.imdb.com/title/tt0118655/">Dr. Evil</a>: “Lasers.” </p>
<p>Lasers focus a narrow, directed beam of light on a specific spot, making them a great tool for cutting, burning, welding – or in the case of Dr. Evil, shooting enemies from atop a shark. These activities all produce or require heat. Laser beams travel at the speed of light, more than 670 million miles per hour, making them the fastest thing in the universe.</p>
<p>So how does a laser produce the slowest thing on Earth? </p>
<p>First, it’s important to understand the relationship between an object’s temperature and its speed. The hotter something is, the more energy it has and the faster it moves. Even things that appear to be perfectly still – say, a pen or your notebook – are not. On a microscopic level, the particles they’re made of are moving rapidly. This is even true of living beings.</p>
<p>Let’s use the sloth as an example. If you zoom in on the molecules that make up this famously slow animal’s body, you’ll see them behaving like kids jumping around inside a bounce house. Why? About <a href="https://doi.org/10.2307/1379840">70% of this creature’s body is made up of water</a> and those water molecules are bouncing around at <a href="https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Map%3A_Physical_Chemistry_(McQuarrie_and_Simon)/18%3A_Partition_Functions_and_Ideal_Gases/18.11%3A_The_Equipartition_Principle">hundreds of miles per hour</a>.</p>
<h2>Laser cooling</h2>
<p>So it might seem surprising that I use bright, intense lasers to cool things down in my lab experiments. <a href="https://scholar.google.com/citations?user=rm6lxY0AAAAJ&hl=en&oi=sra">I am a physicist</a> who is interested in how atoms and molecules behave at the very coldest temperatures. It’s a strange world where quantum mechanics rules. In this realm, particles sometimes behave like waves in the ocean, and believe it or not, can sometimes be in two different places at the same time. </p>
<p>To study this extraordinary behavior, I use lasers to produce clouds of frigid atoms that are the coldest things on Earth – which we call <a href="https://www.britannica.com/science/Bose-Einstein-condensate">Bose-Einstein condensates</a>. When you cool a bunch of atoms down to almost absolute zero, the coldest possible temperature, atoms start to obey quantum mechanics and behave in surprising ways. </p>
<p>Studying ultra-cold atom clouds might provide clues about how other weird materials, <a href="https://theconversation.com/physicists-hunt-for-room-temperature-superconductors-that-could-revolutionize-the-worlds-energy-system-80707">like superconductors</a>, work. Superconductors carry electricity much better than existing materials, so well that they may someday be used to build super high-speed trains.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/340717/original/file-20200609-21208-18v2oum.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In 1995, researchers cooled atoms lower than ever before and created a new state of matter that had been predicted by Albert Einstein. This graphic shows snapshots as the atoms condensed from more spread-out red, yellow and green areas into very dense blue and white areas.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Quantum_Physics;_Bose_Einstein_condensate_(5940505475).jpg#/media/File:Quantum_Physics;_Bose_Einstein_condensate_(5940505475).jpg">NIST/JILA/CU-Boulder</a></span>
</figcaption>
</figure>
<h2>Creating the slowest thing on Earth</h2>
<p>So how exactly do lasers chill out a cloud of atoms? In the lab, we start by shining lasers at atoms of a silvery-white metal called ytterbium. These atoms, which are really hot, are held inside a 1-foot-wide chamber. But after a few seconds under the laser beam, they cool off, slow down and become trapped together in the center of the chamber. </p>
<p>How does this happen? All light, including a laser, is made up of photons, which are packets of energy that are constantly moving. When we shine a laser into our chamber, the atoms collide with streams of photons in the beam and slow down and get colder – like what would happen if you tried running really fast against a strong wind.</p>
<p>These little collisions bring the temperature of the atom cloud down to just a few millionths of a degree above absolute zero. That’s 459 degrees below 0 degrees Fahrenheit.</p>
<p>But that’s still not enough to give this cloud the prize for being the slowest thing on Earth. It takes one last step to make it just a little colder, a technique we physicists call “<a href="https://www.sciencedirect.com/science/article/pii/S1049250X08601019">evaporative cooling</a>.” </p>
<p>First, we capture all the atoms, sometimes using a magnetic field made by running electricity through a wound-up wire. This creates an invisible well that holds the atoms: Picture marbles sitting at the bottom of a bowl. Then we lower the sides of this bowl-shaped force field by decreasing the electric current that runs through the wire. That allows the faster, warmer atoms to zoom out of the “bowl” and escape the trap. </p>
<p>Only the slower atoms are left behind – and they are truly beyond freezing: one-tenth of one-millionth of a degree above absolute zero. The atoms in this cloud move in slow motion: If they traveled in a straight line instead of bouncing around, it would take them an entire hour to travel across a room. For comparison, the molecules in your body could dash across that room in just a fraction of a second.</p>
<p>The atoms in our frigid atom cloud quite literally move at less than a snail’s pace – and that cloud is the slowest thing on Earth.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/132827/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Katie McCormick does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Physicists can use bright, hot lasers to slow atoms down so much that they measure -459 degrees Fahrenheit.Katie McCormick, Postdoctoral Scholar of Physics, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1353782020-04-03T18:01:11Z2020-04-03T18:01:11ZBlue dye from red beets – chemists devise a new pigment option<figure><img src="https://images.theconversation.com/files/324753/original/file-20200401-23143-1032w4i.jpg?ixlib=rb-1.1.0&rect=233%2C170%2C1715%2C1386&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Through the wonders of chemistry, molecules can be rearranged to completely transform color.</span> <span class="attribution"><span class="source">Erick Leite Bastos</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>What’s your favorite color? If you answered blue, you’re in good company. <a href="https://today.yougov.com/topics/lifestyle/articles-reports/2015/05/12/why-blue-worlds-favorite-color">Blue outranks all other color preferences</a> worldwide by a large margin.</p>
<p>No matter how much people enjoy looking at it, blue is a difficult color to harness from nature. As a chemist who <a href="https://www.bastoslab.com/">studies the modification of natural products</a> to solve technological problems, I realized there was a need for a safe, nontoxic, cost-effective blue dye. So my Ph.D. student, Barbara Freitas-Dörr, and I devised a <a href="https://advances.sciencemag.org/content/6/14/eaaz0421">method to convert the pigments of red beets into a blue compound</a> that can be used in a wide range of applications. We call it BeetBlue.</p>
<h2>Natural sources of blue</h2>
<p>Blue is strongly associated with nature, largely because it is reflected in the sky and on bodies of water. But compared to other colors, blue pigments are not commonly found in living organisms.</p>
<p>The feathers of many birds are blue, not because they produce a pigment, but because the microscopic structure of their <a href="https://en.wikipedia.org/wiki/Structural_coloration">feathers is able to filter light</a>. This physical phenomenon is very interesting but difficult to adopt for common applications.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/324747/original/file-20200401-23130-yhy2og.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The <em>Lactarius indigo</em> mushroom is one of Mother Nature’s rare examples of blue.</span>
<span class="attribution"><a class="source" href="https://de.wikipedia.org/wiki/Datei:2013-08-06_Lactarius_indigo_(Schwein.)_Fr_359786.jpg">Alan Rockerfeller/Mushroom Observer</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Plants seldom produce blue hues. When they do, their pigments rarely remain stable after extraction. The same is true for blue mushrooms like the indigo milky cap and other species that develop a blue stain when disturbed. </p>
<h2>Turning red into blue</h2>
<p>You might wonder how something red can be turned into something blue. One approach is to change the way its molecules absorb and reflect light.</p>
<p>The white light coming from your lamp contains a rainbow of colors, even though you cannot see them – without the use of a prism, that is. The surface of your red chair looks red because, at the molecular level, it is absorbing all the colors except red, which is reflected and eventually reaches your eyes.</p>
<p>The color of your chair would change from red to blue if you modified the molecular structure of its dye, making it reflect blue light instead of red. The secret is in the number of carbon atoms in the dye and how they are connected to each other. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=148&fit=crop&dpr=1 600w, https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=148&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=148&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=185&fit=crop&dpr=1 754w, https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=185&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/325053/original/file-20200402-74889-mrhg0p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=185&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">By changing the structure of molecular compounds, you can alter color.</span>
<span class="attribution"><span class="source">Erick Leite Bastos</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Beets produce chemical compounds called betalains, which are natural pigments and antioxidants. The chemical structure of betalains can be modified to produce almost any hue. We realized that if we increased the number of alternating single-double bonds in betalain molecules, we could change their color from orange or magenta to blue.</p>
<p>Making blue dye with adequate intensity and light-fastness is difficult because it must absorb yellow and orange light efficiently. Solving this problem required lots of molecular tweaking.</p>
<p>My lab has been working with betalains for over 10 years to understand their function in nature and their unique chemical features, so it took only one experiment to produce BeetBlue. (It took more than two years to optimize the process, though.) </p>
<p>We broke apart the betalain molecules using alkaline water with a pH of 11. Then we mixed the resulting compound, called betalamic acid, with a commercial chemical compound called 2,4-dimethylpyrrole in an open vessel at room temperature. BeetBlue is formed almost instantly. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/FUS95BYqJ24?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">BeetBlue is created in a beaker at room temperature.</span></figcaption>
</figure>
<p>Because we changed the characteristic carbon-nitrogen chemical bond of betalains into a carbon-carbon bond, BeetBlue is a new class of pseudo-natural dyes we call quasibetalains.</p>
<h2>Color your life blue</h2>
<p>The chemical synthesis of BeetBlue is fast and very simple. In fact, it is so simple that anyone can do it if all the chemicals are available.</p>
<p>BeetBlue dissolves easily in water and other solvents, maintains its color in acidic and neutral solutions, and may provide an alternative to expensive blue colorants that often <a href="https://en.wikipedia.org/wiki/List_of_inorganic_pigments#Blue_pigments">contain toxic metals</a>, which limit the scope of their applications. </p>
<p>Live zebrafish embryos as well as cultured human cells were not affected by BeetBlue. Although more experiments are necessary to make sure it is safe for human consumption, maybe you can dye your hair, customize your clothes or color your food in the future using a dye made from beets.</p>
<p>This work shows the importance of basic science for the development of technological applications. We did not patent BeetBlue. We want people to use it freely and understand, by interacting with nature in a different and sustainable way, the future can be bright. </p>
<p>[<em>Insight, in your inbox each day.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=insight">You can get it with The Conversation’s email newsletter</a>.]</p><img src="https://counter.theconversation.com/content/135378/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Erick Leite Bastos receives funding from the São Paulo Research Foundation (FAPESP), the Brazilian National Council for Scientific and Technological Development (CNPq), and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).</span></em></p>A simple chemical reaction turns the red pigment of beets into a new, nontoxic blue dye.Erick Leite Bastos, Associate Professor of Chemistry, Universidade de São Paulo (USP)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1175382019-05-28T11:10:42Z2019-05-28T11:10:42ZCurious Kids: how long has gravity existed?<figure><img src="https://images.theconversation.com/files/276775/original/file-20190528-42600-gdbw65.jpg?ixlib=rb-1.1.0&rect=23%2C0%2C2346%2C1476&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Gravity helps stars to form. </span> <span class="attribution"><a class="source" href="http://www.esa.int/spaceinimages/Images/2017/02/Star_formation_on_filaments_in_RCW106">UNIMAP / L. Piazzo, La Sapienza – Università di Roma; E. Schisano / G. Li Causi, IAPS/INAF, Italy</a>, <a class="license" href="http://artlibre.org/licence/lal/en">FAL</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/au/topics/curious-kids-36782">Curious Kids</a> is a series by <a href="https://theconversation.com/uk">The Conversation</a>, which gives children of all ages the chance to have their questions about the world answered by experts. All questions are welcome: you or an adult can send them – along with your name, age and town or city where you live – to curiouskids@theconversation.com. We won’t be able to answer every question, but we’ll do our best.</em></p>
<hr>
<p><em><strong>How long has gravity existed? - Aine, aged 13, Edinburgh, UK.</strong></em></p>
<p>Gravity is <a href="https://www.esa.int/kids/en/learn/Earth/Natural_disasters/What_Is_Gravity">a force</a> between two masses, so gravity exists wherever there is mass. To discover when gravity started to exist, we need to understand what mass is, and when it started to exist. </p>
<p>Let’s dive right in: “mass” is what we use to measure how much “matter” there is. Scientists use <a href="http://www.chem4kids.com/files/matter_intro.html">the term “matter”</a> to describe stuff like stars, planets, oceans, rocks, molecules, atoms, particles like electrons and protons that make up atoms, and even the particles that make up electrons and protons.</p>
<p>Very nearly everything you encounter in everyday life counts as “matter”: a book, a glass of water, a bird – anything you might also call “stuff”. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-is-everything-really-made-of-molecules-109145">Curious Kids: is everything really made of molecules?</a>
</strong>
</em>
</p>
<hr>
<p>There are <a href="https://theconversation.com/curious-kids-is-everything-really-made-of-molecules-109145">some exceptions</a>: for example, neither light nor sound is matter, nor are feelings. Light can even travel through completely empty space, where there’s no matter at all. </p>
<p>If a feather and a football are both made of matter, you might wonder why they’re so different. Well, a football has much more matter than a feather, so we’d say its “mass” is higher. </p>
<p>On the other hand, a kilogram of feathers and a kilogram of iron have the same mass because they weigh the same – even though the feathers take up a lot more space. </p>
<p>If you could count every particle in your body, then you could add up all of their masses and you would have a measure of your own mass. </p>
<h2>Mass, weight and gravity</h2>
<p>Of course, that isn’t how we actually measure masses in real life. Here on Earth, we measure mass via weight. Mass and weight are not quite the same thing, but they are related. </p>
<p>If you took a scale to the moon and weighed yourself on it, the number it showed would be smaller than when you weighed yourself on the Earth – even though your mass is still the same, your weight would change. This is because the scale you use is actually not measuring your mass directly, but rather the gravitational force your mass is feeling from the Earth, or the moon.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=576&fit=crop&dpr=1 600w, https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=576&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=576&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=724&fit=crop&dpr=1 754w, https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=724&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/276778/original/file-20190528-42556-4yguri.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=724&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">You weigh less on the moon.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/sites/default/files/thumbnails/image/apollo08_earthrise.jpg">NASA.</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>How strong gravity is <a href="https://www.esa.int/kids/en/learn/Earth/Natural_disasters/What_Is_Gravity">depends on</a> the mass of both objects, as well as the distance between them. Because the Earth has a lot more mass than the moon, the force of gravity you experience on Earth is stronger. That’s why you weigh more on Earth than on the moon. </p>
<h2>A cosmic creation</h2>
<p>So, when did mass first appear? Based on our best understanding of the physics of the universe, the first mass was created in the form of tiny particles (a LOT of them) right after the beginning of the universe itself, about <a href="https://www.esa.int/kids/en/learn/Our_Universe/Story_of_the_Universe/The_Big_Bang">13.7 billion years ago</a>.</p>
<p>The creation of matter happened so fast after the creation of the universe that you could fit more than a million of those instants in the time it takes to blink an eye. And from that moment, gravity was at work, pulling matter together, gathering atoms and molecules into dense clouds that eventually formed stars and galaxies and planets.</p>
<p>Of course, there are <a href="https://physics.info/newton-first/">many forces</a> in nature, and gravity is only one of them. The other forces work on matter too, so there has always been a cosmic dance between the different forces in the universe, which makes it look how it does. </p>
<p>Gravity might be the force that we’re all most familiar with because we all have felt it since the moment we were born, but actually compared to many of the other forces it’s not especially strong. </p>
<p>But since gravity is found anywhere there is mass, it’s basically everywhere, at all times. </p>
<p>The same gravity that keeps you on the ground here on Earth also holds the Earth together, holds the Earth in orbit around the sun, and holds the sun in orbit around the rest of the galaxy. </p>
<p>Gravity has existed for as long as the universe has, and it will keep existing, for as long as we do, and beyond. </p>
<hr>
<p><em>More <a href="https://theconversation.com/topics/curious-kids-36782?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Curious Kids</a> articles, written by academic experts:</em></p>
<ul>
<li><p><em><a href="https://theconversation.com/curious-kids-why-do-we-lose-our-baby-teeth-111911?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Why do we lose our baby teeth? - Jack, age 8.</a></em></p></li>
<li><p><em><a href="https://theconversation.com/curious-kids-why-do-pets-have-dark-eyes-while-humans-have-mostly-white-eyes-115391?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Our guinea pigs have dark eyes. Why do we have white eyes? - Rhoswen, aged three, Bristol, UK.</a></em></p></li>
<li><p><em><a href="https://theconversation.com/curious-kids-how-was-the-earth-made-112067?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">How was the Earth made? - Audrey, age 5.</a></em></p></li>
</ul><img src="https://counter.theconversation.com/content/117538/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brooke Simmons has previously received funding from the National Aeronautics and Space Administration (NASA) to research galaxies, which are mentioned in this article. </span></em></p>Gravity exists because the universe is full of ‘stuff’ – here’s how it came to be.Brooke Simmons, Lecturer in Astrophysics, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1091452019-01-09T12:48:29Z2019-01-09T12:48:29ZCurious Kids: is everything really made of molecules?<figure><img src="https://images.theconversation.com/files/252701/original/file-20190107-32154-zq4nrg.jpg?ixlib=rb-1.1.0&rect=121%2C87%2C4369%2C3009&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Is this it?</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/little-girl-elementary-school-constructs-model-1089743798">Shutterstock.</a></span></figcaption></figure><p><em><a href="https://theconversation.com/au/topics/curious-kids-36782">Curious Kids</a> is a series for children of all ages, where The Conversation asks experts to answer questions from kids. All questions are welcome: find out how to enter at the bottom of this article.</em> </p>
<hr>
<blockquote>
<p><strong>People say that everything is made of molecules. Are feelings made of molecules? Is sound made of molecules? – Claire, age six, Bristol, UK</strong></p>
</blockquote>
<p>Thanks for the question, Claire. First things first: when people say “everything”, often they actually mean the stuff that scientists call “matter”. Matter is stuff you can touch. But feelings are not matter, and neither is sound. </p>
<p>Things that are matter include stars, air, water, tables, chairs, trees, your body, your brain, and pretty much everything that you see around you. </p>
<p>All of these things are made up of molecules – but molecules aren’t the smallest pieces of matter, because every molecule is made up of <a href="http://particleadventure.org/">even smaller pieces</a> called atoms. </p>
<p>And atoms themselves are made up of even tinier pieces. One of the tiniest types of pieces that makes up matter is called the electron. </p>
<h2>Electrons and emotions</h2>
<p>Things that are not matter include feelings, thoughts and light. Light allows us to see all of the things around us, but it’s different from matter. The main difference is that it doesn’t weigh anything. Even air has a weight, but light doesn’t.</p>
<p>Feelings and thoughts also don’t have a weight, and are not matter. But they’re not light, either. Feelings and thoughts live inside our brains. </p>
<p>The way that the matter in our brains acts <a href="https://science.howstuffworks.com/life/inside-the-mind/human-brain/5-ways-your-brain-influences-your-emotions.htm">affects our feelings and thoughts</a>, and our feelings and thoughts can affect the way the matter in our brain acts. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=386&fit=crop&dpr=1 600w, https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=386&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=386&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=485&fit=crop&dpr=1 754w, https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=485&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/252502/original/file-20190104-32121-3n3ufm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=485&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Feelings aren’t matter, but your brain is.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/asian-child-girl-green-concrete-wall-646493059?src=CjrH8uCLN5iO1fdkA9cvJQ-1-7">Shutterstock.</a></span>
</figcaption>
</figure>
<p>Scientists don’t yet know exactly how thoughts are made, but they do know that it has something to do with the way those tiniest pieces of matter – electrons – move around to create <a href="https://learn.genetics.utah.edu/content/neuroscience/neurons/">an electrical signal</a>, like the signals that are sent from a light switch to turn a light on. </p>
<p>For example, scientists have found out that your brain <a href="https://www.livescience.com/32798-how-are-memories-stored-in-the-brain.html">holds on to memories</a> by keeping electrons in certain places. </p>
<p>There are different kinds of feelings. There are feelings that your body tells you, like when you burn your finger on a candle or when you feel hungry. And there are feelings that we call emotions, like when you’re sad or excited. </p>
<p>Both kinds of feelings are made in your brain and both kinds have to do with those electrons again, with how they move and where they sit in your brain.</p>
<h2>Sensing sound</h2>
<p>Sound is a different thing again. Sound is made of waves, but not really like waves on the ocean. <a href="https://www.physicsclassroom.com/mmedia/waves/lw.cfm">Soundwaves are created</a> when the molecules around us move in a certain way. </p>
<p>Imagine you’re playing some loud music through a speaker. If you touch the front of a speaker while the music’s playing, you should be able to feel it jiggle.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/mZURZtkf9WM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>The jiggle of the speaker causes the molecules in the air around it to jiggle and bump into each other. </p>
<p>That little jiggle causes the other molecules nearby to jiggle, and the jiggles pass from one group of air molecules to another, until they finally reach the air molecules next to your ear drum. </p>
<p>Your ear drum is very sensitive, and can tell that the air molecules are jiggling, so it sends a special message to your brain. Your brain gets the message and says, “that’s music!” – and that’s <a href="https://www.nidcd.nih.gov/health/how-do-we-hear">how you hear</a> the song. </p>
<p>So, neither feelings nor sound are made of molecules in the same way that matter is. But they both have a lot to do with the way molecules – and their smaller parts, atoms and electrons – move around. </p>
<hr>
<p><em>Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. You can:</em></p>
<p><em>* Email your question to curiouskids@theconversation.com
<br>
* Tell us on <a href="https://twitter.com/ConversationUK">Twitter</a> by tagging <a href="https://twitter.com/ConversationEDU">@ConversationUK</a> with the hashtag #curiouskids, or
<br>
* Message us on <a href="https://www.facebook.com/ConversationUK/">Facebook</a>.</em></p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><em>Please tell us your name, age and which town or city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won’t be able to answer every question, but we will do our best.</em></p>
<hr>
<p><em>More <a href="https://theconversation.com/topics/curious-kids-36782?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Curious Kids</a> articles, written by academic experts:</em></p>
<ul>
<li><p><em><a href="https://theconversation.com/curious-kids-is-it-true-dogs-dont-like-to-travel-108670?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Is it true dogs don’t like to travel? – Ankush, India</a></em></p></li>
<li><p><em><a href="https://theconversation.com/curious-kids-how-do-eyes-grow-108489?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">How do eyes grow? – Annette, age seven, Stratford-upon-Avon, UK</a></em></p></li>
<li><p><em><a href="https://theconversation.com/curious-kids-who-were-the-spartans-108606?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Who were the Spartans? – Trystan, a young reader from Australia</a></em></p></li>
</ul><img src="https://counter.theconversation.com/content/109145/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laura Kormos does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Everything you can touch is made of molecules – but feelings, sound and light are something different.Laura Kormos, Senior Lecturer in Physics, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1068862018-12-05T12:14:18Z2018-12-05T12:14:18ZProteins reveal intricate details about life under the microscope<figure><img src="https://images.theconversation.com/files/247492/original/file-20181127-76737-1ae515d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A 3D rendering of an orange carotenoid protein, whose secrets are slowly being unlocked.</span> <span class="attribution"><span class="source">ibreakstock/Shutterstock</span></span></figcaption></figure><p>People have always been fascinated by life. We dream about revealing all its mysteries and are even searching other planets trying to find some forms of life there. Philosophies around the world have tried to define and understand life long before science even existed. But some of the answers may actually be found right under our noses – or rather, right under a microscope.</p>
<p>That’s because an entire world exists at the bio-molecular level. Without it, life as we know and understand it wouldn’t exist. </p>
<p>Proteins are among the key players in this bio-molecular world. They do their job by binding to each other or to other molecules to achieve their genetically pre-programmed goals. For instance, a protein complex called <a href="https://www.ebi.ac.uk/interpro/potm/2005_10/Page1.htm">haemoglobin</a> delivers oxygen to every cell of our bodies to perform respiration. Almost every action involves an interaction between protein complexes.</p>
<p>The aim of our work was to uncover a very fundamental detail of life at the bio-molecular level. For the first time, we were able <a href="https://pubs.acs.org/doi/abs/10.1021/acs.jpclett.8b00767?journalCode=jpclcd&">to describe at a detailed level</a> how two proteins, as they exist in nature, interact with each other and how they behave in their own molecular worlds. </p>
<p>It’s no easy task to actually watch life at the molecular level, and to see individual proteins at work. We managed to do this using <a href="https://theconversation.com/how-the-discovery-of-a-proteins-secret-function-could-boost-solar-tech-98407">a technique</a> called single molecule spectroscopy, which allows scientists to investigate the properties of individual molecules.</p>
<h2>Single proteins at work</h2>
<p>Under the spectroscope, we explored a unique biochemical system that protects photosynthetic bio-molecular machinery – and the whole organism – from lethal levels of the sun, for example on a cloudless day at noon. </p>
<p>Photosynthesis is a complex, potentially dangerous process: photosynthetic organisms can die when exposed to too much light. This may sound odd, given that such organisms need light to survive. But it’s an excellent example of how too much of a good thing can turn bad. This is why photosynthetic organisms have photoprotective mechanisms, which shield them from too much light.</p>
<p>These mechanisms use various proteins to regulate the amount of energy flowing through the photosynthetic apparatus.</p>
<p>In these systems, it’s the interactions between some proteins that determine whether an organism will survive under the full sun or not. And while these systems do the same job – removing the excessive energy from the photosynthetic apparatus in a safe way – they work differently in different organisms.</p>
<p>Our latest <a href="https://pubs.acs.org/doi/abs/10.1021/acs.jpclett.8b00767?journalCode=jpclcd&">work</a> allowed us to see how one of these photoprotective mechanisms operates. We studied at an incredible level of detail, one at a time, the protein “antennae” that are responsible for the harvesting of light. Doing so led to an important discovery.</p>
<p>We already knew that the main photoprotective mechanism in cyanobacteria involves the binding of a protein called orange carotenoid protein onto the photosynthetic light-harvesting “antenna”. This work also revealed that the binding is a complex process which involves an intermediate step. </p>
<h2>A simple model</h2>
<p>A simple experiment helps to explain this process and the crucial intermediate step.</p>
<p>Imagine a staircase built from a few toy bricks with a small container placed below the lowest stair. Take the whole system out in the rain – and watch how water is collected on the stairs, then goes down until it finally falls into the container.</p>
<p>In our experiment, the rain represents the sunlight and the staircase works conceptually like a photosynthetic antenna. The water is collected on the stairs in the same way solar energy is in the photosynthetic antennae. The energy remains in the antenna until reaching the so-called reaction centre, where the light energy is converted into a more stable form of energy.</p>
<p>Because the staircase is made out of bricks, it’s not waterproof. It leaks: the water drips on the floor at different places instead of reaching the container. In the same way, the photosynthetic antennae leaks a small fraction of energy. </p>
<p>By observing these “leakages” using spectroscopy, we have learned about the intricate details of the photosynthetic process. </p>
<p>In heavy rainfall, too much water would go down your stairs and overflow the container. The equivalent situation – intense rays of sunlight – is potentially deadly for photosynthetic organisms; they must work hard to avoid this. That’s where photoprotective mechanisms come in.</p>
<p>The mechanisms we studied work as if they were collecting water from the stairs and safely removing it before it reaches the container. In cyanobacteria’s photosynthetic apparatus, orange carotenoid protein acts as the “collector”. Our work shows how this protein is inserted into the photosynthetic apparatus to get rid of harmful, excess absorbed light energy.</p>
<p>For this insertion to happen, part of the cyanobacteria’s antenna system actually detaches for a short time. This allows the orange carotenoid protein to “dock”: it binds tightly to the antenna so it can start to effectively remove dangerous excess energy. This step was completely unknown and could only have been accessed using single molecule spectroscopy.</p>
<h2>New knowledge</h2>
<p>This new knowledge helps us to understand and appreciate how complicated life is even at the basic bio-molecular level. Advanced experimental methods like single molecule spectroscopy bring this mysterious world of bio-molecules closer to us and show how important it is for the functioning of organisms on Earth.</p><img src="https://counter.theconversation.com/content/106886/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michal Gwizdala receives funding from The University of Pretoria and previously received funding from EU via Marie Sklodowska Curie Actions ITN Harvest, European Molecular Biology Organisation via Long-Term Fellowship, VU Amsterdam and Claude Leon Foundation via Post-doctoral Fellowship.</span></em></p><p class="fine-print"><em><span>Tjaart Krüger receives funding from the University of Pretoria, the National Research Foundation and the Department of Science and Technology.</span></em></p>When two proteins interact with each other they behave in their own molecular lives.Michal Gwizdala, Postdoctoral researcher in photosynthesis, Vrije Universiteit AmsterdamTjaart Krüger, Associate Professor in Biophysics, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1048382018-10-22T19:13:46Z2018-10-22T19:13:46ZA day to celebrate chemistry’s favorite unit — the mole. But what’s a mole?<figure><img src="https://images.theconversation.com/files/240889/original/file-20181016-165888-1rbw6m2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Mole Day is an unofficial holiday celebrated among chemists on Oct. 23, between 6:02 a.m. and 6:02 p.m. The time and date are derived from Avogadro's number.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/reminder-mole-day-calendar-unofficial-holiday-639554344">Ekaterina_Minaeva/Shutterstock.com</a></span></figcaption></figure><p>On Oct. 23, between 6:02 a.m. and 6:02 p.m., chemists celebrate Mole Day. Mole Day is not a day to celebrate those furry little creatures that live in the ground. Rather, it is a day to celebrate a very important idea in the sub-microscopic world. </p>
<p>In chemistry, the mole is a unit used to talk about atoms. It is similar to other units we use everyday. For example, you might walk into the local doughnut shop and order a dozen doughnuts. In doing so, you know that you will get 12 of these snacks and the clerk knows to give you 12. The dozen unit is simply for convenience in discussing a quantity. </p>
<p>We apply the same idea to discuss quantities of atoms. Why do we not simply talk about dozens of atoms? The reason is because atoms are so small that it doesn’t make sense to do so. Imagine a single grain of table salt. That tiny crystal contains over 1,000,000,000,000,000,000 (one quintillion) atoms. Rather than discussing such a large number of atoms, we can talk more conveniently through the mole unit. A mole of something contains 602,000,000,000,000,000,000,000 or 6.02 x 10²³ of that thing. </p>
<p>So rather than talking about over 1,000,000,000,000,000,000 atoms in the grain of salt, we can express the quantity as around 0.000002 moles of atoms, which is much more convenient.</p>
<p>The number 6.02 x 10²³ is also called Avogadro’s number. Amedeo Avogadro was an Italian physicist. In 1811, he proposed that equal volumes of any gas at the same temperature and pressure contain the same number of atoms (or molecules). The number is named after him to honor his work. Because Oct. 23 is abbreviated as 10/23, chemists use this date to celebrate Mole Day. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=331&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=331&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=331&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=415&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=415&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241541/original/file-20181021-105748-xmwdoy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=415&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Amedeo Avogadro predicted that equal volumes of different gases would contain the same number of molecules.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/avogadros-hypothesis-balloons-340098266?src=sZ9AiRkhU9H5_ym02VaO2g-1-1">magnetix / Shuterstock.com</a></span>
</figcaption>
</figure>
<h2>How much space does a mole occupy?</h2>
<p>Now just how many is 6.02 x 10²³? How long do you think it would take you to count to a mole? One day? One week? One year? Go ahead, start counting. It would take you around 20,000,000,000,000,000 years. As you can see, very large quantities of atoms take up very little space which gives us an idea of just how tiny they are. Here is another example: One mole of water with all 6.02 x 10²³ molecules of H₂O occupies slightly more than a tablespoon. </p>
<p>So how do those tiny atoms come together to make up the stuff in the world around us? Even though atoms are so small, there is a lot of action going on. Each atom is made up of even smaller particles called electrons. The way those electrons place themselves around the atom lead to properties we can experience and observe. In a metal, the tiny atoms are swimming in a sea of electrons which gives them the ability to conduct heat and electricity. </p>
<p>How about water? The electrons in a molecule of water are arranged so that each water molecule is extremely attracted to the one next to it. Because of this they naturally arrange themselves at the atomic level in ways that have big consequences in the world around us. When water freezes, the molecules arrange in a way that creates a lattice that causes ice to float in liquid water. Why is that so important? Because ice floats, a pond or lake will freeze at the top, but below the entire aquatic ecosystem is able to survive. This is an amazing phenomenon of water. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=306&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=306&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=306&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=385&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=385&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241542/original/file-20181021-105773-g2nxfx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=385&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Atoms are made up of even smaller particles called protons, neutrons and electrons. The arrangement of these particles gives each substance specific properties.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/simplest-atomic-model-hydrogen-carbon-oxygen-1022007508?src=q1VjPFk6YNxYoapF9IhEbA-1-31">Nasky / Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Small atoms with big consequences</h2>
<p>Many other substances adopt their own unique properties due to arrangement of electrons. The propane gas that we use to fuel a gas grill is a gas at room temperature because the molecules are weakly attracted to each other. Unlike water, they don’t really want to be next to each other at all. Consequently, the space between them results in a gaseous state. </p>
<p>Another important gas is oxygen. We need oxygen to live out our lives. Close your eyes and take a deep breath. As you do that, the molecules are whizzing through your nose, into your lungs where about 0.001 moles of oxygen are absorbed into your blood. Those molecules are responsible for helping each cell in your body produce energy so that your eyes can see the words on this page and your brain can think about what they mean, all while keeping your heart beating.</p>
<p>So, if you ever feel like you’re too insignificant to make a difference, just remember that even the smallest of things matter in the grand scheme of things. </p>
<p>Happy Mole Day!</p><img src="https://counter.theconversation.com/content/104838/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Chemists sure know how to party. And here is the proof. On October 23rd they celebrate their hallowed unit: the mole. Find out what that’s all about.Tara S. Carpenter, Senior Lecturer and General Chemistry Coordinator, University of Maryland, Baltimore CountyGabriella Balaa, Assistant researcher, University of Maryland, Baltimore CountyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1004902018-08-02T09:59:01Z2018-08-02T09:59:01ZCurious Kids: what is fire?<figure><img src="https://images.theconversation.com/files/230070/original/file-20180731-136679-4urkrl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/jameswest/5079424994/sizes/l">Westy48/Flickr.</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p><em>This is an article from <a href="https://theconversation.com/au/topics/curious-kids-36782">Curious Kids</a>, a series for children of all ages. The Conversation is asking young people to send in questions they’d like an expert to answer. All questions are welcome: find details on how to enter at the bottom.</em> </p>
<hr>
<blockquote>
<p><strong>What is fire? – Lyra, age seven, Oxford, UK</strong></p>
</blockquote>
<hr>
<p>Thanks for the question, Lyra. Basically, fire is light and heat that comes from a special kind of chemical reaction, which humans figured out how to make hundreds of thousands of years ago. </p>
<p>To understand how that reaction works, there are a few things that we need to learn about the world around us. Everything that you see and touch is made up of tiny things called atoms. You can think of atoms as really, really small bits of Lego – so small you can’t even see them. </p>
<p>Atoms join together to form molecules, and molecules join together to form the objects we can see and feel in everyday life. For example, wood is mainly made of a type of molecule called <a href="http://www.bbc.co.uk/guides/z2d2gdm">cellulose</a> and each molecule of cellulose is made of atoms called carbon, oxygen and hydrogen.</p>
<p>Now, to see how the chemical reaction works, let’s imagine that you’re living in a cave <a href="https://www.history.com/news/human-ancestors-tamed-fire-earlier-than-thought">400,000 years ago</a>, and that you’re one of the very first people to use fire. </p>
<p>You’re hungry and you want to cook an animal that you caught earlier in the day. On your way back to the cave, you collected some twigs and sticks for your fire. But there’s two other things you need before you can light the fire. You need oxygen – but luckily there’s plenty of that in the air (though you wouldn’t have known about it at the time). And you’ll need some heat to start things burning.</p>
<p>Of course, matches haven’t been invented yet, so instead you quickly rub two sticks together. The rubbing causes friction, which heats up the sticks – like when you rub your hands together fast to warm them up. This heat causes all the molecules in the wood to jiggle around. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/230072/original/file-20180731-136670-1pc4i5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Where there’s smoke…</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/traditional-way-starting-fire-seen-namibia-603688799?src=kYWAB-T379wXBY8sCVHjvQ-2-46">Shutterstock.</a></span>
</figcaption>
</figure>
<p>When a part of a stick gets hot enough, the molecules are moving about so much they start to break apart. This is when you start to see smoke. The smoke is all those broken up molecules escaping from the wood as gases.</p>
<p>But you haven’t made fire yet – you need things to get even hotter! So you keep rubbing the sticks together really hard. Eventually, the gas molecules from the wood get so hot they bash into oxygen in the air and join together. When they do that, they make new molecules called water and carbon dioxide. At the same time, they also make heat and light. Well done, you’ve made a flame! You can stop rubbing the sticks together now. </p>
<p>As you put more twigs on your small fire, the heat carries on breaking down the molecules in the wood, and making more gases. These gases catch fire as well. But something else needs to happen before your fire can really grow. When the gases leave the wood you get left with charcoal. Then, as your fire gets even hotter, the charcoal also starts to combine with more oxygen, making even more heat and light. Now things are hot enough to start cooking.</p>
<p>You make your meal, and after a while you run out of fuel for your fire. All the wood and charcoal burns away leaving ash. This is the stuff in the wood that doesn’t burn. Without the light and heat from the fire, there’s nothing to do but go to sleep – but at least you’re not hungry anymore. </p>
<p><em>Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. You can:</em></p>
<p><em>* Email your question to curiouskids@theconversation.com
<br>
* Tell us on <a href="https://twitter.com/ConversationUK">Twitter</a> by tagging <a href="https://twitter.com/ConversationEDU">@ConversationUK</a> with the hashtag #curiouskids, or
<br>
* Message us on <a href="https://www.facebook.com/ConversationUK/">Facebook</a>.</em></p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165749/original/image-20170419-32713-1kyojyz.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><em>Please tell us your name, age and which town or city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won’t be able to answer every question, but we will do our best.</em></p>
<hr>
<p><em>More <a href="https://theconversation.com/topics/curious-kids-36782?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">Curious Kids</a> articles, written by academic experts:</em></p>
<ul>
<li><p><em><a href="https://theconversation.com/curious-kids-how-do-sim-cards-make-a-phone-work-96273?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">How do SIM cards make a phone work? – Leo, age 5, Sydney</a></em></p></li>
<li><p><em><a href="https://theconversation.com/curious-kids-whats-it-like-to-be-a-fighter-pilot-100563?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">What’s it like to be a fighter pilot? – Torben, age eight, Sussex, UK</a></em></p></li>
<li><p><em><a href="https://theconversation.com/curious-kids-if-an-insect-is-flying-in-a-car-while-it-is-moving-does-the-insect-have-to-move-at-the-same-speed-98833?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=CuriousKidsUK">If an insect is flying in a car while it is moving, does the insect have to move at the same speed? – Sarah, age 12, Strathfield, Australia</a></em></p></li>
</ul><img src="https://counter.theconversation.com/content/100490/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Lorch does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Put simply, it’s the outcome of a chemical reaction, which humans learned how to make some 400,000 years ago.Mark Lorch, Professor of Science Communication and Chemistry, University of HullLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/947842018-04-16T09:00:24Z2018-04-16T09:00:24ZChamomile tea may help control diabetes – as my research into 19th century dyes revealed<figure><img src="https://images.theconversation.com/files/214733/original/file-20180413-587-9zyay1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/cups-chamomile-tea-flowers-on-wooden-276983174?src=vVC5iBBz8-VRwT2LMZwJKA-1-51">ConstantinosZ/Shutterstock.com</a></span></figcaption></figure><p>Chamomile – that yellow flower so often made into a tea, enjoyed before bed – is a very interesting plant. It was recently discovered that the humble flower may control or even prevent diabetes – and now <a href="https://www.nature.com/articles/s41598-018-23736-1">my research</a> into historical textile dyes has helped to identify the specific compounds involved. That bedtime herbal tea may be doing many people a lot of good.</p>
<p>I’ve been working with Chris Rayner for over 15 years to develop new techniques to identify the chemistry of natural colourants used throughout history to dye textiles. Before William Perkin’s serendipitous 1856 <a href="http://www.rsc.org/Chemsoc/Activities/Perkin/2006/minisite_perkin_mauveine_non_flash.html">discovery of mauveine</a>, the first synthetic dye, textile fibres were dyed with coloured extracts of plants and animals. </p>
<p>Nature makes a complex cocktail of different compounds in these dye plants, and many of these are transferred to textiles during dyeing. We analyse historical artefacts to see if these compounds are present to try to determine when, where and how they were dyed and with what plant. The chemistry and ratio of these molecules can provide significant information about which plant species was used to dye the fibres or the technique used for the dye process. In the context of historical textiles, this information is of paramount importance for conservation and restoration purposes, as well as the generation of information on the ethnographic origins of the artefacts.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=653&fit=crop&dpr=1 600w, https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=653&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=653&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=821&fit=crop&dpr=1 754w, https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=821&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/214741/original/file-20180413-127631-1hmy9iu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=821&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Dyeing wool cloth, 1482.</span>
<span class="attribution"><span class="source">British Library Royal MS 15.E.iii, folio 269</span></span>
</figcaption>
</figure>
<p>So what does this have to do with diabetes? Well, many of the techniques that have been used to extract the dyes from textile samples cause damage to the dye molecule, resulting in a loss of information about the chemical fingerprint potentially available to conservators. But we have developed <a href="https://www.sciencedirect.com/science/article/pii/S0021967317301383">new “soft” extraction methods using glucose</a>, which can preserve the dye molecule during extraction and analysis, and have used these new techniques to investigate dyes that were commonly used prior to the mid-19th century.</p>
<p>One such plant used throughout history was chamomile, which gives a bright yellow colour on wool, cotton and other natural fibres. There is <a href="http://pubs.rsc.org/en/content/articlelanding/2004/cs/b305697j">evidence</a> of its use in Europe and Asia to dye textiles dating back many hundreds of years. We identified the colourants and other natural components present in several species of chamomile in our attempts to understand their coloration properties and their identification in historical textiles, in the process significantly developing our knowledge of their complex chemistry.</p>
<p>This would have been interesting from a pure conservation and dye chemistry perspective. But then members of our team had a chat with another research group, led by Professor Gary Williamson in the School of Food Science and Nutrition, and it became apparent that we had a mutual interest in the chemistry of chamomile. </p>
<p>As a food, most people will be familiar with chamomile’s use as a herbal tea, often associated with aiding sleep. Indeed recognition of its medicinal properties as a relaxant and sedative is exemplified by its listing as an <a href="https://journals.lww.com/hnpjournal/Citation/2008/01000/Chamomile__A_Spoonful_of_Medicine.10.aspx">official drug</a> in the pharmacopoeias of 26 countries, including the UK. But we didn’t realise that it potentially has other dietary benefits. German chamomile has been taken for digestive problems <a href="http://www.rjb.csic.es/jardinbotanico/ficheros/documentos/pdf/pubinv/RMV/354Chapter14book.pdf">since at least the first century CE</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/214739/original/file-20180413-584-enbg0b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">German chamomile.</span>
<span class="attribution"><span class="source">JSOBHATIS16899/Shutterstock.com</span></span>
</figcaption>
</figure>
<p>This team has spent the last few years studying the link between dietary components and carbohydrate digestion: specifically, how certain natural compounds can help to control blood glucose levels. They had screened several plant extracts and <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/mnfr.201700566">identified</a> German chamomile (<em>Matricaria chamomilla</em>) as very effective in controlling diabetes in 2017. But what was really important was to understand which compounds in particular were responsible for this activity. We wondered if our research on natural dyes in chamomile could help with this.</p>
<p>We applied the techniques that we had developed for extraction of historical textiles to extraction and analysis of chamomile flowers. Working together, we identified four specific compounds that are active in chamomile and able to control carbohydrate digestion, drawing on our experience of dyestuff analysis. </p>
<p>Two of these compounds, apigenin-7-<em>O</em>-glucoside and apigenin, are yellow colourants that we had previously seen in wool textiles dyed with chamomile. The other two compounds had been previously misidentified by other researchers, but we correctly identified them as (<em>Z</em>) and (<em>E</em>)−2-hydroxy-4-methoxycinnamic acid glucosides. We studied the contribution of these four compounds to the overall bioactivity of chamomile, and found that, taken together, they were able to modulate carbohydrate digestion and absorption. There is also the potential to extract and concentrate these components from chamomile for medicinal application.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/214742/original/file-20180413-587-tc0oxx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Chamomile chemical structures.</span>
<span class="attribution"><span class="source">Richard Blackburn</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>So simply put, drinking chamomile tea may be helpful in controlling or even preventing diabetes. And excitingly, it seems that understanding the chemistry of plant dyes in common use prior to the mid-19th century could unlock new treatments for modern day medicine.</p><img src="https://counter.theconversation.com/content/94784/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard Blackburn receives funding from BBSRC, Clothworkers’ Foundation, DEFRA, EPSRC, Innovate UK and National Institute for Health Research. He is affiliated with The Society of Dyers and Colourists and The American Chemical Society. </span></em></p>That pre-sleep herbal tea may be doing many people a lot of good.Richard Blackburn, Associate Professor and Head of The Sustainable Materials Research Group, University of LeedsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/904102018-01-30T11:32:08Z2018-01-30T11:32:08ZPromising male birth control pill has its origin in an arrow poison<figure><img src="https://images.theconversation.com/files/203914/original/file-20180130-89590-1n68uqn.jpg?ixlib=rb-1.1.0&rect=351%2C0%2C2144%2C1470&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Will blue packets replace pink ones soon?</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/male-contraceptive-pill-746870245">Aleksandra Berzhets/Shutterstock.com</a></span></figcaption></figure><p>After decades of research, development of a male birth control may now be one step closer. My colleagues and I are working on a promising lead for a <a href="https://doi.org/10.1021/acs.jmedchem.7b00925">male birth control pill based on ouabain</a> – a plant extract that African warriors and hunters traditionally used as a heart-stopping poison on their arrows.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/203915/original/file-20180130-89582-1h4a3d8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Hunters want ouabain to be deadly when used on an arrow, but no one wants a fatal contraceptive.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/poison-on-arrow-784275280">PLANET EARTH/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>State of the search</h2>
<p>While the birth control pill has been available to women in the United States for nearly six decades – and FDA-approved for <a href="http://www.mum.org/enovid-e.htm">contraceptive use since 1960</a> – an oral contraceptive for men has not yet come to market. The pill has provided women with safe, effective and reversible options for birth control, while options for men have been stuck in a rut.</p>
<p>Today, <a href="https://doi.org/10.4103/2230-8210.102991">men have just two choices</a> when it comes to birth control: condoms or a vasectomy. Together, these two methods account for just <a href="https://www.malecontraceptive.org/why-male-contraception-dr-john-amory/">30 percent of contraception used</a>, leaving the remaining 70 percent of contraceptive methods to women. An estimated <a href="https://doi.org/10.21037/tau.2017.07.22">500,000 American men opt for a vasectomy each year</a> – a small number given the need for contraception. Vasectomy is an invasive procedure to do that’s also difficult and invasive to reverse.</p>
<p>When it comes to birth control options for men, the need is clear. <a href="https://www.ncbi.nlm.nih.gov/pubmed/23689167">Unplanned pregnancy rates</a> remain high across the globe. It’s time for more options.</p>
<h2>Hormonal versus nonhormonal</h2>
<p>Researchers are exploring both hormonal and nonhormonal options for male birth control pills. Current <a href="https://doi.org/10.1002/14651858.CD004316.pub2">hormonal agents under study</a> involve the sex steroids progestins and testosterone.</p>
<p>While the male hormonal birth control pill option <a href="https://doi.org/10.1210/jc.2016-2141">is in clinical human trials</a> and likely closer to market, it has <a href="https://doi.org/10.1097/MED.0b013e3282fcc30d">several potential side effects</a>: In addition to potentially causing weight gain and changes in libido, it has the ability to lower the levels of good cholesterol (HDL-C) in men, which could negatively affect the heart health of users. The long-term effects of using hormones for male oral contraception are unknown, and it will likely be decades before this information is available.</p>
<p>Here at the University of Minnesota, my colleagues and I have focused on <a href="https://doi.org/10.1016/j.pep.2016.01.009">nonhormonal contraception methods</a> that <a href="https://doi.org/10.1002/cmdc.201700503">work by targeting</a> <a href="https://doi.org/10.1038/35098027">sperm motility</a> – biology-speak for the sperms’ ability to move or swim effectively. <a href="https://en.wikipedia.org/wiki/Sperm_motility">Good motility</a> is a necessary condition for fertilizing a female egg.</p>
<p>In collaboration with <a href="http://www.kumc.edu/school-of-medicine/molecular-and-integrative-physiology/faculty/faculty/v-gustavo-blanco-md-phd.html">Gustavo Blanco</a> at the University of Kansas, we’ve homed in on ouabain: a toxic substance produced by two types of African plants. Mammals also produce ouabain in their bodies, though at lower nonlethal levels that scientists think can help control blood pressure. In fact, physicians have used ouabain in very small doses to treat patients with heart arrhythmias or suffering from heart attacks.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=285&fit=crop&dpr=1 600w, https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=285&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=285&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=358&fit=crop&dpr=1 754w, https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=358&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/203870/original/file-20180129-89577-4p34d8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=358&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A cross-section of a cell membrane shows how pumps made of protein subunits move sodium and potassium ions in and out of the cell.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:0308_Sodium_Potassium_Pump.jpg">OpenStax</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>From toxin to contraceptive</h2>
<p>Researchers know that ouabain disrupts the passage of sodium and potassium ions through cell membranes; it interferes with the proper function of proteins that transport the ions in and out of cells. Some of the ion-transporting protein subunits targeted by ouabain are found in cardiac tissue – its ability to disrupt proper heart function is what makes ouabain a deadly poison. But ouabain also affects another type of transporter subunit called α4, which is found only in sperm cells. This protein is known to be <a href="https://doi.org/10.1073/pnas.1016902108">critical in fertility</a> — at least in male mice.</p>
<p>For 10 years, my colleagues and I have been studying ouabain as a potential breakthrough in our quest for a male birth control pill. However, ouabain by itself isn’t an option as a contraceptive because of the risk of heart damage. So we set out to design ouabain analogs – versions of the molecule that are more likely to bind to the α4 protein in sperm than other subunits in heart tissue.</p>
<p>In the lab, we used the techniques of <a href="https://www.acs.org/content/acs/en/careers/college-to-career/chemistry-careers/medicinal-chemistry.html">medicinal chemistry</a> to create a derivative of ouabain that is good at zeroing in on the α4 transporter in sperm cells in rats. Once bound to those cells, it interferes with the sperms’ ability to swim – essential to its role in fertilizing an egg. Our new compound showed no toxicity in rats.</p>
<p>Because the α4 transporter is found only on mature sperm cells, the contraceptive effect should be reversible – sperm cells produced after stopping the treatment presumably won’t be affected. Ouabain may also offer men a birth control pill option with fewer systemic side effects than hormonal options.</p>
<h2>Next steps on the road to drug discovery</h2>
<p>Our results are promising because our candidate molecule, unlike ouabain, is nontoxic in rats. Our modification is a big step forward in the process of developing a nonhormonal male birth control pill. But there’s a lot left to do before men can buy this contraceptive at the pharmacy.</p>
<p>After our ouabain analog showed <a href="https://doi.org/10.1530/REP-09-0495">promise in rat studies</a> at reducing sperm motility, future studies will focus on the effectiveness of our lead compound as an actual contraceptive in animals. We need to prove that a reduction in sperm movement translates into a drop in egg fertilization.</p>
<p>Then, we’ll begin the standard steps in drug discovery such as toxicology and safety pharmacology studies as we advance toward planning and conducting clinical trials. Our team is already taking the next step to <a href="https://doi.org/10.1095/biolreprod.106.057810">test our compound in animal mating trials</a>. If things continue as planned, we hope to get to human clinical trials within five years.</p>
<p>Reversible, effective male birth control is within sight. World Health Organization numbers suggest that <a href="https://doi.org/10.1093/humupd/dmp048">reducing sperm motility by 50 percent or less</a> is sufficient to temporarily make a man infertile. Our ongoing research brings us one step closer to expanding the options for male birth control, providing the world’s 7.6 billion people with a much-needed option for safe and reversible contraception.</p><img src="https://counter.theconversation.com/content/90410/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This research was funded by the National Institutes of Health Eunice Kennedy Shriver National Institute of Child Health and Human Development.</span></em></p>Medicinal chemists are tweaking a natural molecule that can be a deadly poison – a modified version might work as a nonhormonal male contraceptive.Gunda Georg, Professor of Medicinal Chemistry and Director of the Institute for Therapeutics Discovery and Development, University of MinnesotaJon Hawkinson, Research Professor of Medicinal Chemistry and Associate Program Director of the Institute for Therapeutics Discovery and Development, University of MinnesotaShameem Syeda, Principal Scientist at the Institute for Therapeutics Discovery and Development, University of MinnesotaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/811222017-07-24T08:06:31Z2017-07-24T08:06:31ZBooze in space: how the universe is absolutely drowning in the hard stuff<figure><img src="https://images.theconversation.com/files/179195/original/file-20170721-18128-14pw7he.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Mine's a Star-opramen. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/retro-astronaut-mug-beer-pop-art-486571996?src=GRArIRYoATk-qqeZn7VeGg-1-7">Studioloks</a></span></figcaption></figure><p>A cold beer on a hot day or a whisky nightcap beside a coal fire. A well earned glass can loosen your thinking until you feel able to pierce the mysteries of life, death, love and identity. In moments like these, alcohol and the cosmic can seem intimately entwined. </p>
<p>So perhaps it should come as no surprise that the universe is awash with alcohol. In the gas that occupies the space between the stars, the hard stuff is almost all-pervasive. What is it doing there? Is it time to send out some big rockets to start collecting it?</p>
<p>The chemical elements around us reflect the history of the universe and the stars within it. Shortly after the Big Bang, protons were formed throughout the expanding, cooling universe. Protons are the nuclei of hydrogen atoms and building blocks for the nuclei of all the other elements. </p>
<p>These have mostly been manufactured since the Big Bang through nuclear reactions in the hot dense cores of stars. Heavier elements such as lead or gold are only fabricated in rare massive stars or incredibly explosive events. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=835&fit=crop&dpr=1 600w, https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=835&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=835&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1050&fit=crop&dpr=1 754w, https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1050&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/179175/original/file-20170721-18110-oqdban.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1050&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Ethanol molecule.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:Ethanol-3D-balls.png#/media/File:Ethanol-3D-balls.png">Wikimedia</a></span>
</figcaption>
</figure>
<p>Lighter ones such as carbon and oxygen are synthesised in the life cycles of very many ordinary stars – including our own sun eventually. Like hydrogen, they are among the most common in the universe. In the vast spaces between the stars, <a href="https://ay201b.wordpress.com/2011/04/12/course-notes/">typically</a> 88% of atoms are hydrogen, 10% are helium and the remaining 2% are chiefly carbon and oxygen.</p>
<p>Which is great news for booze enthusiasts. Each molecule of ethanol, the alcohol that gives us so much pleasure, includes nine atoms: two carbon, one oxygen and six hydrogen. Hence the chemical symbol C₂H₆O. It’s as if the universe turned itself into a monumental distillery on purpose. </p>
<h2>Interstellar intoxication</h2>
<p>The spaces between stars are known as the interstellar medium. The famous Orion Nebula is perhaps the best known example. It is the closest region of star formation to Earth and visible to the naked eye – albeit still more than 1,300 light years away. </p>
<p>Yet while we tend to focus on the colourful parts of nebulae like Orion where stars are emerging, this is not where the alcohol is coming from. Emerging stars produce intense ultraviolet radiation, which destroys nearby molecules and makes it harder for new substances to form. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=587&fit=crop&dpr=1 600w, https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=587&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=587&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=737&fit=crop&dpr=1 754w, https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=737&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/179190/original/file-20170721-18113-gcen2i.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=737&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Orion Nebula.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Orion_Nebula#/media/File:Orion_Nebula_-_Hubble_2006_mosaic_18000.jpg">Wikimedia</a></span>
</figcaption>
</figure>
<p>Instead you need to look to the parts of the interstellar medium that appear to astronomers as dark and cloudy, and only dimly illuminated by distant stars. The gas in these spaces is <a href="http://casswww.ucsd.edu/archive/public/tutorial/ISM.html">extremely cold</a>, slightly less than -260°C, or about 10°C above absolute zero. This makes it very sluggish. </p>
<p>It is also fantastically widely dispersed. At sea level on Earth, by my calculations there are roughly 3x10<sup>25</sup> molecules per cubic metre of air – that’s a three followed by 25 zeros, an enormously huge number. At passenger jet altitude, circa 36,000ft, the density of molecules is about a third of this value – say 1x10<sup>25</sup>. We would struggle to breathe outside the aircraft, but that’s still quite a lot of gas in absolute terms. </p>
<p>Now compare this to the dark parts of the interstellar medium, where there are typically 100,000,000,000 particles per cubic metre, or 1x10<sup>11</sup>, and often much less than even that. These atoms seldom come close enough to interact. Yet when they do, they can form molecules less prone to being blown apart by further high-speed collisions than when the same thing happens on Earth. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/179196/original/file-20170721-18165-1tl87lr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The proof is out there.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/very-bright-white-star-named-procyon-412689028?src=sMN_naWxfUHYuErfk0iKOQ-2-44">Tragoolchitr Jittasaiyapan</a></span>
</figcaption>
</figure>
<p>If an atom of carbon meets an atom of hydrogen, for instance, they can stick together as a molecule called <a href="https://link.springer.com/referenceworkentry/10.1007%2F978-3-642-11274-4_1807">methylidyne</a> (chemical symbol CH). Methylidyne is highly reactive and so is quickly destroyed on Earth, but it is common in the interstellar medium. </p>
<p>Simple molecules like these are more free to encounter other molecules and atoms and slowly build up more complex substances. Sometimes molecules will be destroyed by ultraviolet light from distant stars, but this light can also turn particles into slightly different versions of themselves called <a href="http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa/bonding/ionic_bondingrev1.shtml">ions</a>, thereby slowly expanding the range of molecules that can form. </p>
<h2>Soot and fire water</h2>
<p>To make a nine-atom molecule such as ethanol in these cool and tenuous conditions might still take an extremely long time – certainly much longer than the seven days you might ferment home brew in the attic, let alone the time it takes to walk to the liquor store. </p>
<p>But there is help at hand from other simple organic molecules, which start sticking together to form grains of dust, something like soot. On the surfaces of these grains, chemical reactions take place much more rapidly because the molecules get held in proximity to them. </p>
<p>It is therefore cool sooty regions, the potential stellar birthplaces of the future, that encourage complex molecules to appear more quickly. We can tell from the distinctive spectrum lines of different particles in these regions that there is water, carbon dioxide, methane and ammonia – but also plenty of ethanol. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=693&fit=crop&dpr=1 600w, https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=693&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=693&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=871&fit=crop&dpr=1 754w, https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=871&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/179199/original/file-20170721-18148-1xqq9en.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=871&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Room for more!</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/almost-empty-beer-glass-isolated-on-453410167?src=zWSyEpcHcissj_TKI0sNcA-1-76">Africa Studio</a></span>
</figcaption>
</figure>
<p>Now when I say plenty, you have to bear in mind the vastness of the universe. And we are still only <a href="http://adsabs.harvard.edu/doi/10.1086/168830">talking about</a> roughly one in every 10m atoms and molecules. Suppose you could travel through interstellar space holding a pint glass, scooping up only alcohol as you moved. To collect enough for a pint of beer you would have to travel about half a million light years – much further than the size of our Milky Way. </p>
<p>In short, there are mind-bogglingly vast quantities of alcohol in outer space. But since it is dispersed over truly enormous distances, the drinks companies can rest easy. It will be a cold day on the sun before we figure out how to collect any of it, I’m sorry to say.</p><img src="https://counter.theconversation.com/content/81122/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexander MacKinnon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It’s like one great big distillery up there.Alexander MacKinnon, Senior Lecturer, Astrophysics, University of GlasgowLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/747282017-03-22T18:33:37Z2017-03-22T18:33:37Z3-D printing turns nanomachines into life-size workers<figure><img src="https://images.theconversation.com/files/162085/original/image-20170322-12437-jb8bq0.jpg?ixlib=rb-1.1.0&rect=125%2C107%2C3628%2C2005&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Molecular machines are ready to join forces and take on real-world work.</span> <span class="attribution"><span class="source">Chenfeng Ke</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Nanomachines are tiny molecules – more than 10,000 lined up side by side would be narrower than the diameter of a human hair – that can move when they receive an external stimulus. They can already <a href="http://www.pnas.org/content/102/29/10029">deliver medication</a> within a body and serve as <a href="http://www.nature.com/nature/journal/v445/n7126/full/nature05462.html">computer memories</a> at the microscopic level. But as machines go, they haven’t been able to do much physical work – until now. </p>
<p><a href="http://www.keresearchgroup.com">My lab</a> has used nano-sized building blocks to <a href="http://onlinelibrary.wiley.com/doi/10.1002/anie.201612440/full">design a smart material</a> that can perform work at a macroscopic scale, visible to the eye. A 3-D-printed lattice cube made out of polymer can lift 15 times its own weight – the equivalent of a human being lifting a car.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Au9ruZ6Kfh0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Our polymer is able to lift an aluminum plate when chemical energy is added in the form of a solvent.</span></figcaption>
</figure>
<h2>Nobel-winning roots are rotaxanes</h2>
<p>The design of our new material is based on <a href="https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/">Nobel Prize-winning research</a> that turned mechanically interlocked molecules into work-performing machines at nanoscale – things like <a href="http://doi.org/10.1126/science.1094791">molecular elevators</a> and <a href="http://doi.org/10.1038/nature10587">nanocars</a>.</p>
<p>Rotaxanes are one of the most widely investigated of these molecules. These dumbbell-shaped molecules are capable of converting input energy – in the forms of light, heat or altered pH – into molecular movements. That’s how these kinds of molecular structures got the nickname “<a href="https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/popular-chemistryprize2016.pdf">nanomachines</a>.”</p>
<p>For example, in a molecule called [2]rotaxane, composed of one ring on an axle, the ring can move along the axle to perform shuttling motions. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=196&fit=crop&dpr=1 600w, https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=196&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=196&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=246&fit=crop&dpr=1 754w, https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=246&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/161663/original/image-20170320-9129-oe7dbi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=246&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Left, a [2]rotaxane. The ring can shuttle along the axle. Right, representation of billions of [2]rotaxanes in solution. The motions of nano-rings counteract macroscopically.</span>
<span class="attribution"><span class="source">Chenfeng Ke</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>So far, harnessing the mechanical work of rotaxanes has been very challenging. When billions of these tiny machines are randomly oriented, the ring motions will cancel each other out, producing no useful work at a macroscale. In order to harness these molecular motions, scientists have to think about controlling their three-dimensional arrangement as well as synchronizing their motions. </p>
<h2>Molecular beads on a string</h2>
<p>Our design is based on a well-investigated family of molecules called polyrotaxanes. These have multiple rings on a molecular axle. In our new material, the ring is a cyclic sugar and the axle is a polymer. </p>
<p>If we provide an external stimulus – like adding water – these rings randomly shuttling back and forth can instead stick to each other and form a tubular array. When that happens, it changes the stiffness of the molecule. It’s like when beads are threaded onto a string; many beads slid together make the string much stronger, like a rod.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=123&fit=crop&dpr=1 600w, https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=123&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=123&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=154&fit=crop&dpr=1 754w, https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=154&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/161664/original/image-20170320-9114-1ugcsh3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=154&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cartoon presentation of a polyrotaxane. The rings are changed from the shuttling state, left, to the stationary state, right.</span>
<span class="attribution"><span class="source">Chenfeng Ke</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Our approach is to build a polymer system where billions of these molecules become stronger with added water. The strength of the whole architecture is increased and the structure can perform useful work.</p>
<p>In this way, we were able to get around the original problem of the random orientation of many nanomachines together. The addition of water locks them into a stationary state, therefore strengthening the whole 3-D architecture and allowing the united molecules to perform work together. </p>
<h2>3-D printing the material</h2>
<p>Our research is the first to add 3-D printability to mechanically interlocked molecules. It was integrating the 3-D printing technique that allowed us to transform the random shuttling motions of nano-sized rings into smart materials that perform work at macroscopic scale.</p>
<p>Getting the molecules all lined up in the right orientation is a way to amplify their motions. When we add water, the rings of the polyrotaxanes stick together via hydrogen bonds. The tubular arrays then stack together in a more ordered manner.</p>
<p>It’s much easier to get the molecules coordinated while they’re in this configuration as opposed to when the rings are all freely moving along the axle. We were able to successfully print lattice-like 3-D structures with the rings locked into position in this way. Now the molecules aren’t just randomly positioned within the material.</p>
<p>After 3-D-printing out the polymer, we used a photo-curing process – similar to the UV lamp that hardens nail polish at a salon – to cure it. We were left with a material that had good 3-D structural integrity and mechanical stability. Now it was ready to do some work.</p>
<h2>Shape changing back and forth</h2>
<p>The three-dimensional geometry of the polymer is crucial for its shape changing. A hollow structure is easier to deform than a solid one. So we designed a lattice cube structure to maximize its shape-deformation ability and, in turn, its ability to do work as it switched back and forth from one state to the other.</p>
<p>The next important step was being able to control the work our polymer could do.</p>
<p>It turns out the complex 3-D architecture of these structures can be reversibly deformed and reformed. We were able to use a solvent to switch the threaded ring structure between random shuttling and stationary states at the molecular level. Exchanging the solvent let us easily repeat this shape-changing and recovery behavior many times.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/5h6CzJb9BqM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Squirting in solvent adds chemical energy to our polymer. As the solvent evaporated over time, the polyrotaxane returned to its original form.</span></figcaption>
</figure>
<p>This is how we converted chemical energy into mechanical work.</p>
<p>Just like moving beads to strengthen or weaken a string, this shape-changing is critical because it allows the amplification of molecular motion into macroscopic motion.</p>
<p>A 3-D printed lattice cube made of this smart material lifted a small coin 1.6 millimeters. The numbers may sound small for our day-to-day world, but this is a big step forward in the effort to get nanomachines doing macro work.</p>
<p>We hope <a href="http://onlinelibrary.wiley.com/doi/10.1002/anie.201612440/full">this advance</a> will enable scientists to further develop smart materials and devices. For example, by adding contraction and twisting to the rising motion, molecular machines could be used as soft robots performing complicated tasks similar to what a human hand can do.</p><img src="https://counter.theconversation.com/content/74728/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chenfeng Ke does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Research on molecular machines won last year’s Nobel Prize in chemistry. Now scientists have figured out a way to get these tiny molecules to join forces and collaborate on real work on a macro scale.Chenfeng Ke, Assistant Professor of Chemistry, Dartmouth CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/589692016-05-24T13:04:53Z2016-05-24T13:04:53ZPowering nanotechnology with the world’s smallest engine<figure><img src="https://images.theconversation.com/files/123571/original/image-20160523-11025-keou90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Nanobots at work.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>In the minuscule world of <a href="https://theconversation.com/five-ways-nanotechnology-is-securing-your-future-55254">nanotechnology</a>, big steps are rare. But a recent development has the potential to massively improve our lives: an engine measuring 200 billionths of a metre, which could power tiny robots to fight diseases in living cells. </p>
<p>Life itself is proof of the extreme effectiveness of nanotechnology - the manipulation of matter on a molecular or atomic scale - in which DNA, proteins and enzymes can all be considered as machinery. In fact, researchers have managed to make micro-propellers using tiny strands of DNA. These strands can be stitched together so freely and precisely that the practise is known as “<a href="http://www.nature.com/news/2010/100310/full/464158a.html">DNA origami</a>”. However, DNA origami lacks force and operational speed (it takes time measurable in seconds), reducing its robotic function. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122351/original/image-20160512-16431-1o20uun.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Folding DNA.</span>
<span class="attribution"><span class="source">shutterstock</span></span>
</figcaption>
</figure>
<p>But <a href="http://www.pnas.org/content/early/2016/04/27/1524209113">we have now produced nano-engines</a> that can be operated with beams of light to work pistons, pumps and valves. Made from gold nanoparticles bound together by a heat-sensitive chemical, our machines are strong, fast and simple to operate, making them extremely practical for future applications. </p>
<p>One of the biggest problems when dealing with tiny technology is the need to create a strong force for an object at the nanoscale. If you think of a human moving in water, their movements are only slightly restricted and the water feels fluid. But imagine what would happen if that person shrunk to a size one hundred thousand times smaller than an ant. The water would feel incredibly viscous. In order to be able to move with ease at the nanoscale, a “nanoperson” would need to exert an enormous force for their size. The image of an ant, capable of lifting several times its own weight, comes to mind. Hence the name for our discovery: actuating nano-transducers – or ANTs. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=475&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=475&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=475&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=597&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=597&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122356/original/image-20160512-16438-avxi1e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=597&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Strong as an ANT.</span>
<span class="attribution"><a class="source" href="http://www.flickr.com/photos/jurvetson/70704300">Steve Jurvetson</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The ANTs consist of gold nanoparticles bound by a thermo-sensitive material. At room temperature, the binding material is relaxed and can be filled with water, which push the nanoparticles apart. Heated up by just a few degrees using a laser, the material contracts to a thin shell, bringing the nanoparticles closer together and expelling the water. Then as it cools down again, the water rushes back in and repels the nanoparticles with enormous force. The ANTs act as a tiny but powerful spring, storing and releasing large amounts of elastic energy at great speed. </p>
<p>Key to the development of the ANTs was the use of laser light. By choosing the right colour of light for the right size of nanoparticles (in this case green light for gold nanoparticles) it is possible to heat them up very quickly. In darkness, because they are so small, the nanoparticles cool down very quickly as well. The ANTs then can operate within a microsecond. In the same way that light can heat up water to power steam engines, we can use light to build a piston for engines at the nanoscale.</p>
<h2>Exploding ANTs</h2>
<p>“It’s like an explosion,” explains Tao Ding from <a href="http://www.phy.cam.ac.uk/">Cambridge’s Cavendish Laboratory</a>: “We have hundreds of gold balls flying apart in a millionth of a second when water molecules inflate the polymers around them.”</p>
<p>One obvious application for this new advancement will be in the practise of <a href="http://www.southampton.ac.uk/ifls/research/ifls/lifetechnologies/microfluidics.page">microfluidics</a>, which enable an entire chemical lab to exist on a chip. This allows the manufacturing of pharmaceuticals and the analysis of chemicals with very high precision. However, microfluidics have been limited by the need for bulky operating equipment such as pumps and valves which need to be connected physically with pipes to the chip. </p>
<p>The new ANTs can be used as tiny pumps and valves dispersed thought the microfluidic chip itself and operated by small beams of light without the need for any physical connection. Plus, the size of the ANTs (200-400nm) is similar to the size of the smallest spots into which we can focus light, which optimises the technology. Using ANTs would enable much more complex microfluidic designs in the next few years. </p>
<p>We are also looking over the same timescale at using ANTs to produce pistons and eventually engines on a nanoscale, by restricting the motion of the ANTs to a single direction. In the future, such motors could enable us to manufacture specific materials, and eventually even cars and houses, as well as providing the power for nano-engines to work nano-robots inside living cells. Small steps for ANTs could mean big leaps for humans.</p><img src="https://counter.theconversation.com/content/58969/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ventsislav Valev receives funding from The Royal Society. </span></em></p>Explosive developments driving the tiniest engines in the world.Ventsislav Valev, Reader in Physics, University of BathLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/533262016-02-02T12:13:44Z2016-02-02T12:13:44ZConfessions of a chemist: I make molecules that shouldn’t exist<figure><img src="https://images.theconversation.com/files/109799/original/image-20160201-32237-1bof9wc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Shaken not stirred ...</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-324857183/stock-photo-concept-of-chemistry-bookshelf-full-of-books-in-form-of-test-tube-with-chemistry-draw-on.html?src=pd-same_artist-322807478-gmrzSV2APiEo3bGPtztxxA-4">StudioVin</a></span></figcaption></figure><p>At drinks parties and dinners, if someone asks what I do for a living, I always say: “Synthetic chemist … I make new molecules … especially those that shouldn’t exist.” People typically respond that they were not very good at chemistry at school – or they enquire about explosions and smells. And there, usually, the conversation ends.</p>
<p>I worry that chemists are missing a self-promotion trick. While physicists can argue the need to understand the fundamental nature of the universe by studying subatomic particles at the <a href="http://home.cern/topics/large-hadron-collider">Large Hadron Collider</a>, we chemists beaver away using and developing fundamental knowledge of how to connect molecules together. We routinely have to overcome basic <a href="https://www.khanacademy.org/science/chemistry/thermodynamics-chemistry">thermodynamics</a>, which would stop any of us from existing if they controlled the universe – the building blocks of life would simply end up as carbon dioxide, water and ammonia. </p>
<p>I suspect chemistry’s problem is that much of it is just too useful and everyday – though not all of it, as we shall see. Chemistry tends to have recognisable applications such as making drugs, paints, plastic, synthetic fibres and electronics. The Hadron Collider, on the other hand, benefits from looking spectacular and performing abstract feats that’s appeal lies in their distance from the world that we know. </p>
<h2>My work</h2>
<p>For the past 40 years, I have worked on the chemistry of the heavier <a href="http://chemwiki.ucdavis.edu/Inorganic_Chemistry/Descriptive_Chemistry/Elements_Organized_by_Block/2_p-Block_Elements/Group_16%3A_The_Oxygen_Family/1Group_16%3A_General_Properties_and_Reactions">group 16 elements</a>, including sulphur, selenium and tellurium. These have always fascinated me – in part, because the reaction chemistry is quite unpredictable. My early work was on sulphur-nitrogen compounds. Sulphur and nitrogen are quite unusual in that they both exist in nature as their basic elements. With some ingenuity it is possible to form simple compounds containing only them – a classic case of overcoming the thermodynamics that are responsible for the elements being “stable”. </p>
<p>One example is tetrasulphur tetranitride (S<sub>4</sub>N<sub>4</sub>), an orange solid with an interesting cage structure which was first made 180 years ago. The compound is perfectly stable – at least unless there is a tiny bit of heat from friction. That makes it explode violently to give sulphur and nitrogen as thermodynamics takes over. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=629&fit=crop&dpr=1 600w, https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=629&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=629&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=791&fit=crop&dpr=1 754w, https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=791&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/109805/original/image-20160201-32222-znh2ym.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=791&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">OLED on display.</span>
<span class="attribution"><a class="source" href="https://www.google.co.uk/search?client=safari&channel=mac_bm&hl=en&site=imghp&tbm=isch&source=hp&biw=1440&bih=752&q=OLED+television&oq=OLED+television&gs_l=img.3..0j0i24l8.1086.2546.0.2950.15.12.0.0.0.0.99.539.9.9.0....0...1ac.1.64.img..6.9.536.EphRXH1UhKM#q=OLED+television&channel=mac_bm&hl=en&tbm=isch&tbs=sur:fc&imgrc=HEM0D6CLA8yKCM%3A">LG</a></span>
</figcaption>
</figure>
<p>One of the main uses of tetrasulphur tetranitride is as a precursor to creating other sulphur-nitrogen compounds. It can be used, for instance, to prepare a longer chain-like molecule known as a polymer. This is truly alchemy. Known to chemists as polythiazyl, it looks metallic and golden and conducts electricity. </p>
<p>Polythiazyl was in fact the first non-metal material to be <a href="http://pubs.acs.org/doi/abs/10.1021/cr60317a002">found to be</a> a superconductor at low temperatures. This discovery was partly responsible for the whole era of <a href="http://www.colae.eu/what-is-organic-electronics/">organic electronic materials</a>, which apart from winning a <a href="http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2000/">Nobel Prize</a> has given us the likes of <a href="http://www.whathifi.com/news/oled-tv-everything-you-need-to-know">OLED televisions</a>, which need no back light and can therefore be thinner and lighter than other televisions. How ingenious is the synthetic chemist to take two stable highly abundant elements and prepare a simple compound that otherwise would not exist? </p>
<h2>Phosphorus and tellurium</h2>
<p>My group has also worked on phosphorus-sulphur chemistry, which is important in the additives that keep engine oil from turning into tar; and phosphorus-selenium chemistry, which is behind glass-like semiconductors – these might have applications in solar cells in the longer term. <a href="http://onlinelibrary.wiley.com/doi/10.1002/chem.201303884/abstract">Most recently</a> we have been trying to make simple compounds that bond together phosphorus and tellurium (known as P-Te bonds). This is a stupidly hard thing to do. The customary wisdom is that because tellurium is metallic, simple P-Te bonds are bound to simply break and leave you with tellurium metal. To demonstrate otherwise, it took three groups working together in Canada, Germany and the UK. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/109806/original/image-20160201-32254-mqfud4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The building blocks of life.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/wolframburner/3751529776/in/photolist-spwVNd-spEeNt-6Hvz6S-4jLz3a-tKiNaS-2vQ2RQ-2vVkpu-uzBhpK-xWzRQH-w7K35w-yeLnkp-uzBhzp-sFW7z5-spwTqC-sG7n18-Anw2Ep-5dY78J-4sAnt2-9HA7tv-bcG9pV-9HiftY-6uDAoL-6uzorT-dWUQsG-6uDAa3-vbnnqf-vbnkqU-w2JjMf-osfrbr-oaKMdN-osfrjH-yd9U6S-bmMReq-w4zCGq-bx899i-scRSQ6-w5bPcM-v8aYqh-9jB4m7-w5AbQ6-e49fLS-nwjpaf-dWUMvJ">Wolfram Burner</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>I cannot envisage any ready practical application for such compounds, but that certainly doesn’t make it pointless. Learning how to manipulate the structure to stabilise a P-Te bond gives us a fundamental understanding of the forces that hold molecules together and the reaction pathways that can be employed, which is transferable to other problems in chemistry such as making stable materials for the electronics industry. </p>
<p>Along the way we developed new routes to involve certain chemicals in the process. These may prove very valuable for others working in more applied areas (it’s hard to predict what these might be). We learned that an unlikely bond is perfectly possible and can be created in compounds that can be weighed out and put on the shelf. It was also a challenging project for the PhD student who did most of the work.</p>
<p>If you want to understand the art and science of chemistry, this sort of work sums it up – making molecules that shouldn’t exist. It may not lay claim to answering life’s big questions in the same way as physics, but we are still talking about explorations in science that often benefit us in more ways than we can predict. When it comes down to it, the two disciplines are really not so different. </p>
<p>As for my team, now that we have shown what can be done with phosphorus and tellurium, we are wondering: where next? Arsenic-tellurium compounds are even more challenging, so watch this space.</p><img src="https://counter.theconversation.com/content/53326/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Derek Woollins receives funding from the Leverhulme Foundation and EPSRC.</span></em></p>Getting tellurium and phosphorus to form a molecule is stupidly hard and not very glamorous. Here’s why it’s worth the effort.Derek Woollins, Vice Principal (Research) and Provost, University of St AndrewsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/494492015-10-29T11:11:51Z2015-10-29T11:11:51ZHow Minecraft could help teach chemistry’s building blocks of life<figure><img src="https://images.theconversation.com/files/99572/original/image-20151025-27612-z4q7bh.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Viagra rendered in Minecraft.</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>Children should be playing more computer games in school. That idea might enrage you if you think kids today already spend too much time staring at screens or if you are already sick of your offspring’s incessant prattling about fighting zombies and the like. But hear me out. </p>
<p>Specifically, I think more children should be playing the online game Minecraft. <a href="https://minecraft.net/">Minecraft is</a> like a digital version of Lego in which players can construct everything from simple houses to <a href="http://minecraftbuildinginc.com/">intricate fantasy cathedrals</a> and even complex machines such as <a href="http://www.cnet.com/uk/news/minecraft-players-build-working-hard-drives/">mechanical computers</a>. There is no intrinsic aim to the game. Like all good ways of sparking a child’s imagination, it requires them to set their own goals.</p>
<p>But Minecraft is much more than just a game. Used carefully it can also be a <a href="https://theconversation.com/tapping-into-kids-passion-for-minecraft-in-the-classroom-43461">powerful educational tool</a>. It allows young people to create and explore places that are completely inaccessible by other means. Within the blocky world, they can roam around <a href="services.minecraftedu.com/wiki/Wonderful_World_of_Humanities">historical sites</a>, delve into <a href="http://www.bgs.ac.uk/discoveringGeology/geologyOfBritain/minecraft/home.html">the geology</a> beneath their feet or fly through the <a href="http://www.planetminecraft.com/project/heart-for-educational-purposes/">chambers of a heart</a>, and much more besides.</p>
<p>The rich resources of these virtual worlds, coupled with the <a href="http://minecraftedu.com">educational version</a> of the game, allow teachers to immerse young people in a comfortable but exciting learning environment. Minecraft has the ability to bring just about any conceivable structure to the classroom, bedroom or sofa of every player.</p>
<h2>Creating complex structures</h2>
<p>One of the types of structure I’m particularly passionate is that of proteins. These tiny molecular machines fascinate me. They control just about every biological process in your cells and knit your body together. From replicating your DNA and forming the bases of your skin, hair and connective tissue, to digesting food, fighting infections and transporting oxygen around your blood, proteins do it all.</p>
<p>And just like man-made machines, proteins have to be precisely built if they are to do their jobs. A small part out of place, whether a nut in a car left loose by an errant mechanic, or an atom in a protein mutated by UV light, can cause the whole mechanism to fail. Sometimes this will have disastrous consequences: a failed brake in your vehicle, or cancerous cells in your body.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/q-5H9M-drSM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>You don’t have to be interested in biochemistry and its implications to appreciate that proteins are beautiful wonders of nature, just as you can appreciate the elegant design of a car without knowing how it works. The difference is that you can see wonderfully designed cars all the time. But where could you marvel at the structure of a protein? How about Minecraft?</p>
<p>Thanks to the work of my chemistry students and the support of the Royal Society of Chemistry, that is now possible. <a href="http://www2.hull.ac.uk/science/scienceoutreach/MolCraft.aspx">MolCraft</a> is a world where the majestic helices of <a href="http://www.britannica.com/science/myoglobin">myoglobin</a> rise above you. Where you can explore this massive molecule and its iron centre that carries oxygen around your muscles. Or, if you prefer you can fly down <a href="http://www.ks.uiuc.edu/Research/aquaporins/">a pore through which water</a> molecules normally flow across cell membranes. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/99031/original/image-20151020-32258-q9e1qx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Myoglobin in Minecraft.</span>
</figcaption>
</figure>
<p>In MolCraft, anyone can explore the building blocks of these incredible natural nano-machines. You can discover how just 20 chemical building blocks can result in the astonishing diversity of structures and functions that are required to hold living things together. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/99051/original/image-20151020-32258-1tvjzwh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Histidine as seen in Minecraft.</span>
</figcaption>
</figure>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=589&fit=crop&dpr=1 600w, https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=589&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=589&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=740&fit=crop&dpr=1 754w, https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=740&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/99201/original/image-20151021-15449-1y11z0v.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=740&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Histidine as seen by a chemist.</span>
</figcaption>
</figure>
<p>There are plenty of accessible molecular visualisation tools, <a href="http://www.molymod.com/">both physical</a> and <a href="http://www.rcsb.org/pdb/static.do?p=mobile/RCSBapp.html">virtual</a>. But now we’ve used Minecraft to turn the process of exploring and learning about molecules into a game. MolCraft contains a scavenger hunt, quizzes and clues dotted around the world that can be solved with the help of information found during players’ explorations.</p>
<p>Imagine a science lesson where the class is let lose in Minecraft with instructions to find a set of objects hidden on key parts of molecules. Upon retrieving them the teacher will know which molecules each student has explored and what questions they may have answered to find the objects. All this time, the children think they have just been playing a game. </p>
<p>As well as making MolCraft available to <a href="https://universityofhull.box.com/Molcraft">download for free</a>, we’re also working on ways to further integrate the software into education. One idea is to turn it into a complete online learning environment, where students can complete coursework, write assignments, take part in quizzes or help developing other teaching resources, all within the game. Their tutors can then see their work and send them feedback while still immersed in the Minecraft world. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/99571/original/image-20151025-27592-rxjl2f.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The authors posing in front of glycine.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Using Minecraft for teaching doesn’t have to stop at proteins. Our other Minecraft-related projects are allowing students to explore and understand <a href="http://www.english-heritage.org.uk/visit/places/wharram-percy-deserted-medieval-village/">deserted medieval villages</a> or reconstruct the architecture <a href="http://www.hullcraft.com/">of Hull</a> and there’s much more in the pipeline. The only limits are the imagination of teachers and students.</p><img src="https://counter.theconversation.com/content/49449/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Lorch has received funding from the Royal Society of Chemistry (RSC) to develop MolCraft. He is also a member of the RSC.</span></em></p><p class="fine-print"><em><span>Joel Mills works for the University of Hull and as an independent Minecraft consultant. </span></em></p>The online building game offers a way to explore the world of molecules like no other.Mark Lorch, Senior Lecturer in Biological Chemistry, Associate Dean for Engagement , University of HullJoel Mills, Technology enhanced education, University of HullLicensed as Creative Commons – attribution, no derivatives.