tag:theconversation.com,2011:/nz/topics/nanorobots-26841/articlesNanorobots – The Conversation2020-01-19T18:59:43Ztag:theconversation.com,2011:article/1299802020-01-19T18:59:43Z2020-01-19T18:59:43ZNot bot, not beast: scientists create first ever living, programmable organism<p>A remarkable combination of artificial intelligence (AI) and biology has produced the world’s first “living robots”. </p>
<p>This week, a research team of roboticists and scientists <a href="https://www.pnas.org/content/early/2020/01/07/1910837117">published</a> their recipe for making a new lifeform called xenobots from stem cells. The term “xeno” comes from the frog cells (<em>Xenopus laevis</em>) used to make them.</p>
<p>One of the researchers <a href="https://www.forbes.com/sites/simonchandler/2020/01/14/worlds-first-living-robot-invites-new-opportunities-and-risks/#379ef46c3caf">described the creation</a> as “neither a traditional robot nor a known species of animal”, but a “new class of artifact: a living, programmable organism”. </p>
<p>Xenobots are less than 1mm long and made of 500-1000 living cells. They have various simple shapes, including some with squat “legs”. They can propel themselves in linear or circular directions, join together to act collectively, and move small objects. Using their own cellular energy, they can live up to 10 days.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/M18nPjLZrMA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This time-lapse video shows cells being manipulated and assembled to create xenobots. (Original video: Douglas Blackiston, Tufts University)</span></figcaption>
</figure>
<p>While these “reconfigurable biomachines” could vastly improve human, animal, and environmental health, they raise legal and ethical concerns.</p>
<h2>Strange new ‘creature’</h2>
<p>To make xenobots, the research team used a supercomputer to test thousands of random designs of simple living things that could perform certain tasks.</p>
<p>The computer was programmed with an AI “evolutionary algorithm” to predict which organisms would likely display useful tasks, such as moving towards a target. </p>
<p>After the selection of the most promising designs, the scientists attempted to replicate the virtual models with frog skin or heart cells, which were manually joined using microsurgery tools. The heart cells in these bespoke assemblies contract and relax, giving the organisms motion.</p>
<p>The creation of xenobots is groundbreaking.</p>
<p>Despite being described as “programmable living robots”, they are actually completely organic and made of living tissue. The term “robot” has been used because xenobots can be configured into different forms and shapes, and “programmed” to target certain objects – which they then unwittingly seek.</p>
<p>They can also repair themselves after being damaged. </p>
<h2>Possible applications</h2>
<p>Xenobots may have great value.</p>
<p><a href="https://www.technologyreview.com/f/615041/these-xenobots-are-living-machines-designed-by-an-evolutionary-algorithm/">Some speculate</a> they could be used to clean our polluted oceans by collecting microplastics.</p>
<p>Similarly, they may be used to enter confined or dangerous areas to scavenge toxins or radioactive materials.</p>
<p>Xenobots designed with carefully shaped “pouches” might be able to carry drugs into human bodies.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-we-should-welcome-killer-robots-not-ban-them-45321">Why we should welcome 'killer robots', not ban them</a>
</strong>
</em>
</p>
<hr>
<p>Future versions may be built from a patient’s own cells to repair tissue or target cancers. Being biodegradable, xenobots would have an edge on technologies made of plastic or metal.</p>
<p>Further development of biological “robots” could accelerate our understanding of living and robotic systems. Life is incredibly complex, so manipulating living things could reveal some of life’s mysteries — and improve our use of AI.</p>
<h2>Legal and ethical questions</h2>
<p>Conversely, xenobots raise legal and ethical concerns. In the same way they could help target cancers, they could also be used to hijack life functions for malevolent purposes.</p>
<p>Some argue artificially making living things is unnatural, hubristic, or involves “playing God”.</p>
<p>A more compelling concern is that of unintended or malicious use, as we have seen with technologies in fields including nuclear physics, chemistry, biology and AI. </p>
<p>For instance, xenobots might be used for hostile biological purposes prohibited under international law. </p>
<p>More advanced future xenobots, especially ones that live longer and reproduce, could potentially “malfunction” and go rogue, and out-compete other species.</p>
<p>For complex tasks, xenobots may need sensory and nervous systems, possibly resulting in their sentience. A sentient programmed organism would raise additional ethical questions. Last year, the revival of a disembodied pig brain <a href="https://www.nature.com/articles/d41586-019-01216-4">elicited concerns about different species’ suffering</a>.</p>
<h2>Managing risks</h2>
<p>The xenobot’s creators have rightly acknowledged the need for discussion around the ethics of their creation.</p>
<p>The 2018 scandal over using CRISPR (which allows the introduction of genes into an organism) may provide an instructive lesson <a href="https://www.technologyreview.com/s/614761/nature-jama-rejected-he-jiankui-crispr-baby-lulu-nana-paper/">here</a>. While the experiment’s goal was to reduce the susceptibility of twin baby girls to HIV-AIDS, associated risks caused ethical dismay. The scientist in question <a href="https://www.theguardian.com/world/2019/dec/30/gene-editing-chinese-scientist-he-jiankui-jailed-three-years">is in prison</a>.</p>
<p>When CRISPR became widely available, some experts called for a <a href="https://www.theguardian.com/science/2019/mar/13/scientists-call-for-global-moratorium-on-crispr-gene-editing">moratorium</a> on heritable genome editing. Others <a href="https://www.liebertpub.com/doi/10.1089/crispr.2019.0016?utm_source=miragenews&utm_medium=miragenews&utm_campaign=news&">argued</a> the benefits outweighed the risks. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/chinas-failed-gene-edited-baby-experiment-proves-were-not-ready-for-human-embryo-modification-128454">China's failed gene-edited baby experiment proves we're not ready for human embryo modification</a>
</strong>
</em>
</p>
<hr>
<p>While each new technology should be considered impartially and based on its merits, giving life to xenobots raises certain significant questions: </p>
<ol>
<li>Should xenobots have biological kill-switches in case they go rogue?</li>
<li>Who should decide who can access and control them?</li>
<li>What if “homemade” xenobots become possible? Should there be a moratorium until regulatory frameworks are established? How much regulation is required? </li>
</ol>
<p>Lessons learned in the past from advances in other areas of science could help manage future risks, while reaping the possible benefits.</p>
<h2>Long road here, long road ahead</h2>
<p>The creation of xenobots had various biological and robotic precedents. Genetic engineering has created genetically modified mice that become <a href="http://www.understandinganimalresearch.org.uk/news/research-medical-benefits/glowing-mice/">fluorescent</a> in UV light. </p>
<p><a href="https://advances.sciencemag.org/content/1/4/e1500077">Designer microbes</a> can produce drugs and food ingredients that may eventually <a href="https://solarfoods.fi/">replace animal agriculture</a>. </p>
<p>In 2012, scientists created an <a href="https://blogs.scientificamerican.com/brainwaves/what-would-it-take-to-really-build-an-artificial-jellyfish">artificial jellyfish</a> called a “medusoid” from rat cells.</p>
<p>Robotics is also flourishing. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/310613/original/file-20200117-118352-15ylufw.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">Nanobots are tiny robots that carry out specific tasks. In medicine, they can be used for targeted drug delivery.</span>
<span class="attribution"><span class="source">shutterstock</span></span>
</figcaption>
</figure>
<p>Nanobots can <a href="http://news.mit.edu/2013/nanotechnology-could-help-fight-diabetes-0516">monitor people’s blood sugar levels</a> and may eventually be able to <a href="https://www.smithsonianmag.com/innovation/tiny-robots-can-clear-clogged-arteries-180955774/">clear clogged arteries</a>. </p>
<p>Robots can incorporate living matter, which we witnessed when engineers and biologists created a <a href="https://www.sciencemag.org/news/2016/07/robotic-stingray-powered-light-activated-muscle-cells">sting-ray robot</a> powered by light-activated cells.</p>
<p>In the coming years, we are sure to see more creations like xenobots that evoke both wonder and due concern. And when we do, it is important we remain both open-minded and critical.</p><img src="https://counter.theconversation.com/content/129980/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 organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Xenobots have been called the world’s first “living robots”. They are made entirely of living tissue, and can be programmed to move towards a certain object.Simon Coghlan, Senior Research Fellow in Digital Ethics, School of Computing and Information Systems, The University of MelbourneKobi Leins, Senior Research Fellow in Digital Ethics, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/711222017-02-15T15:01:29Z2017-02-15T15:01:29ZFive ways nanoscience is making science fiction into fact<figure><img src="https://images.theconversation.com/files/156965/original/image-20170215-27421-kxpydc.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-illustration/nanotechnology-science-medicine-126734096?src=uxpKWm6hcwfLGg2BCHVkJg-1-44">www.shutterstock.com</a></span></figcaption></figure><p>Russian author Boris Zhitkov wrote the 1931 short story <a href="https://ru.wikisource.org/wiki/%D0%9C%D0%B8%D0%BA%D1%80%D0%BE%D1%80%D1%83%D0%BA%D0%B8_(%D0%96%D0%B8%D1%82%D0%BA%D0%BE%D0%B2)">Microhands</a>, in which the narrator creates miniature hands to carry out intricate surgeries. And while that was nearly 100 years ago, the tale illustrates the real fundamentals of the <a href="http://tmi.utexas.edu/resources/what-is-nanoscience/">nanoscience</a> researchers are working on today. </p>
<p>Nanoscience is the study of molecules that are one billionth of a metre in size. To put this into perspective, a human hair is between 50,000 and 100,000 nanometres thick. At this tiny size, materials possess properties that lie somewhere between a lump of metal and that of a single atom. This unique environment means they can become very reactive and be used as catalysts.</p>
<p>The ideas behind nanoscience are often easier to understand when considered simply in terms of how a single material’s properties change. But the field is not limited to just that: we are now moving into the realm of healthcare therapies, and vehicles smaller than a speck of dust. What were once regarded as science fictions are rapidly becoming fact.</p>
<h2>1. Medi-gels</h2>
<p>In video games like Bioware’s Mass Effect, players are able to heal characters’ injuries with the seemingly miraculous <a href="http://masseffect.wikia.com/wiki/Medi-gel">medi-gel</a>. Though it may not give you the unlimited life or epic adventure that a video game can, there is a real-life gel that can similarly stop an arterial bleed in seconds.</p>
<p>“<a href="https://cresilon.com/index.php/vetigel/">Veti-gel</a>” is made of <a href="http://www.newworldencyclopedia.org/entry/Polysaccharide">polysaccharide polymers</a> found in the cell walls of plants which, when applied to wounds, can mimic the structure of the extracellular matrix – the complex web in which cells sit. The gel essentially acts as scaffolding for the matrix to reform, pulling it back together and stopping bleeding without any pressure. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/e-5wqwp64MM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<h2>2. Healing molecules</h2>
<p>Indeed, wound healing is a key feature of many an action-packed science fiction plot line. Handheld tools have <a href="https://theconversation.com/our-star-trek-style-skin-healing-technology-could-be-the-end-of-chronic-wounds-44608">already been created</a>, similar to Star Trek’s dermal regenerator, to heal injuries.</p>
<p>On the nano-level, a team has developed gel nanoparticles which target a specific enzyme (FL2) which <a href="https://www.ncbi.nlm.nih.gov/pubmed/25756798">slows the migration of skin cells to wounds</a>. They hypothesised that reducing the levels of this enzyme would increase rates of wound healing. </p>
<p>However, delivering the molecules of Silencing RNA (SiRNA) needed to slow the enzyme down would normally be difficult, as unprotected chains of RNA quickly degrade within the body. So these SiRNA molecules were placed inside nano-sized gel shells to aid uptake and their transport into cells. Wounds treated this way healed twice as fast as those which were not, while maintaining normal tissue regeneration. </p>
<h2>3. Self-repairing tech</h2>
<p>The film Terminator 2 features an evil robot that <a href="https://www.youtube.com/watch?v=mTUGXB4i2wI">can repair itself, “healing” in a few seconds</a>. Thankfully, the reality is nowhere near as scary – though we are close to having technology that fixes itself.</p>
<p>Chemists have devised <a href="http://iopscience.iop.org/article/10.1088/0964-1726/23/11/115002">self-healing carbon fibre polymers</a> that break when stress is applied, allowing an epoxy resin to seep from the material and mix with a catalyst. When the resin and catalyst come into contact, a strong plastic with a healing efficiency of up to 108% is formed. The technology is comparable to the healing of a bruise, but instead of bursting a couple of blood vessels, the resin is released. </p>
<p>At a basic level, this may mean that we need never worry about a cracked phone screen again. But it could also <a href="http://www.bbc.co.uk/news/technology-33047859">repair the tiny cracks</a> that develop on planes while they are in flight, or even <a href="http://www.rawstory.com/2015/08/nasa-creates-self-healing-terminator-material-that-can-seal-up-a-bullet-hole-in-2-seconds/">seal bullet holes</a>.</p>
<h2>4. Racing micro-cars</h2>
<p>In 1966, cinema-goers were wowed as the crew of a submarine was shrunk down to microscopic size, and injected into the body of a scientist in the film Fantastic Voyage. Though we are certainly not anywhere near injecting tiny humans into other humans, scientists have created molecular-size vehicles that can be driven in particular directions.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/dO5E4wkg0hA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>In 2011, <a href="https://theconversation.com/from-muscles-to-motors-2016-chemistry-nobel-goes-to-creators-of-the-worlds-tiniest-machines-66596">scientist Ben Feringa</a> constructed a <a href="http://www.nature.com/nature/journal/v479/n7372/full/nature10587.html">four-wheeled nanocar</a>, comprised of four molecular motors on a carbon chain chassis. With wheels only <a href="http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/popular-chemistryprize2016.pdf">60 atoms in size</a> and a width more than 666,666,666 times smaller than a Formula 1 car, it might be hard to <a href="http://www.dailymotion.com/video/x3cr6jv_move-in-atomline_tech">imagine driving</a>, let alone racing, these tiny vehicles. But this year the <a href="http://www.cemes.fr/Molecule-car-Race?lang=en">first two-day nanocar race</a> will take place. Teams will compete on a course made entirely of gold, painstakingly constructed atom by atom. Extra atoms will be placed on the surface to act as obstacles which competitors will have to navigate around.</p>
<h2>5. Fantasy foods</h2>
<p>Roald Dahl’s Charlie and the Chocolate Factory has made millions of mouths water over the years, thanks to the author’s vivid descriptions of quirky tastes and inventive sweets.</p>
<p>In reality, there aren’t chewing gums that taste like a three-course dinner – <a href="http://www.dailymail.co.uk/sciencetech/article-1317950/Willy-Wonka-3-course-meal-stick-chewing-gum-possibility.html">just yet</a> – or fizzy pop that makes you fly. But food manufacturers have been working on ways to change tastes and textures using molecular technology.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/uQkDOs-EtdU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Nanotech has been <a href="https://www.theguardian.com/what-is-nano/nanotechnology-small-food-for-thought">used in food for many years</a> – emulsifiers in mayonnaise, for example – but now scientists are looking at how it can be used to enhance nutrition and the aesthetics of common foods. </p>
<p>Australian bakery Tip-Top are using nanocapsules to <a href="http://www.azonano.com/article.aspx?ArticleID=3226#4">add omega-3 oil to bread</a>. The capsules only open in the correct environment – the stomach – and so can bring the benefits of Omega-3 without the unpleasant taste. Likewise, companies such as Nestle and Unilever are also researching nanocapsules to <a href="http://www.forbes.com/2005/08/09/nanotechnology-kraft-hershey-cz_jw_0810soapbox_inl.html">improve the texture of their food</a>.</p>
<p>Though nano-techology can’t do <a href="https://www.theguardian.com/what-is-nano/nanotechnology-small-food-for-thought">everything that science fiction</a> has promised just yet, it is changing the world as we know it. And the smaller we continue to go, the bigger the potential will be.</p><img src="https://counter.theconversation.com/content/71122/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Josh Davies-Jones 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>Once the subject of fantastical stories, nanoscience is now changing the world as we know it.Josh Davies-Jones, PhD researcher, Cardiff UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/665962016-10-05T14:35:23Z2016-10-05T14:35:23ZFrom muscles to motors: 2016 chemistry Nobel goes to creators of the world’s tiniest machines<p>The 2016 Nobel Prize in Chemistry <a href="http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/press.html?utm_source=twitter&utm_medium=social&utm_campaign=twitter_tweet">has been awarded</a> to three individuals for designing and developing molecular machines. Jean-Pierre Sauvage of France’s University of Strasbourg, J. Fraser Stoddart of Northwestern University in the US and Bernard L. Feringa from the University of Groningen in the the Netherlands will share a sum of US$928,000. </p>
<p>The machines – including motors, pumps and switches – are all on the scale of molecules. It is hoped that such inventions could find use in a range of material and medical applications.</p>
<p>In the 1980s and 90s, Sauvage and Stoddart became the first to efficiently make interlocked molecules, which consist of either interlocked molecular rings (catenanes) or rings of atoms threaded onto an molecular rod (rotaxanes). Critically, both scientists saw the opportunity that such molecules could act as molecular-scale machines, if they could control, for example, the rotation of the rings of a catenane or the shuttling of a ring up and down the rod of a rotaxane. Both went on to achieve this by applying an appropriate stimulus, for example an electrical current or light, which made the interlocked components move relative to one another.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=357&fit=crop&dpr=1 600w, https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=357&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=357&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=449&fit=crop&dpr=1 754w, https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=449&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/140536/original/image-20161005-14215-yq5q6r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=449&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rotaxane crystal structure.</span>
<span class="attribution"><span class="source">M stone at English Wikipedia</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Feringa’s work on molecular machines has focused on developing a family of non-interlocked molecular motors. In these machines, the molecule contains a twisted bond, around which rotation may be modulated by application of an external stimulus as for catenanes and rotaxanes.</p>
<h2>Exciting future</h2>
<p>All three chemists, along with others, have been looking to develop ever more sophisticated and useful examples of molecular machines. A whole range of molecules have been prepared that are chemical versions of real-world machines, including switches, pumps, motors and even cars and elevators. Notably, Sauvage and Stoddart have also developed molecular machines that can reversibly contract like muscles. These typically respond by exposure to different metal ions (charged atoms) or variation in acidity.</p>
<p>The motions in certain molecular machines are accompanied by changes in colour of the molecule, and so they can act as sensors for the stimulus that causes the molecular motion – signalling whenever that specific substance is present. Scientists are also looking to incorporate molecular machines into smart materials so that the motion they can induce in a single molecular machine may then affect the macroscopic material properties. For instance, a sheet of plastic could be made to expand and shrink upon exposure to light or water. </p>
<p>Sauvage, Stoddart and Feringa’s molecular machines are, of course, man-made. Yet there are many examples of amazing functional molecular machines in our own bodies, such as the “motor protein” kinesin and the enzyme ATP synthase, which are essential for a range of biological functions. A truly exciting possibility for the future is the use of lab-produced molecular machines as treatments for diseases that arise from the failure of our own molecular machinery. Molecular machines could also act as delivery agents for drugs, releasing them by undergoing molecular motion when they comes across a stimulus to be found at the appropriate point in the body.</p>
<p>The award of this Nobel Prize reflects the outstanding work that all three scientists and their research teams have contributed to this area of chemical science research, and acts as an inspiration for all those working in the fields of supramolecular chemistry and nanotechnology.</p><img src="https://counter.theconversation.com/content/66596/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nicholas Evans has received funding from EPSRC, Innovate UK, Royal Society and Royal Society of Chemistry.</span></em></p>The smallest motors ever made could one day have a huge impact on our lives.Nicholas Evans, Lecturer in Chemistry, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/581072016-04-21T12:06:08Z2016-04-21T12:06:08ZMeet the nanomachines that could drive a medical revolution<figure><img src="https://images.theconversation.com/files/119474/original/image-20160420-25615-3cz0o8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>A group of physicists recently built the <a href="http://www.popularmechanics.com/science/energy/a20406/single-atom-engine-works/">smallest engine ever created</a> from just a single atom. Like any other engine it converts heat energy into movement – but it does so on a smaller scale than seen before. The atom is trapped in a cone of electromagnetic energy and lasers are used to heat it up and cool it down, which causes the atom to move back and forth in the cone like an engine piston. </p>
<p>The scientists from the University of Mainz in Germany who are behind the invention don’t have a particular use in mind for the engine. But it’s a good illustration of how we are increasingly able to replicate the everyday machines we rely on at a tiny scale. This is opening the way for some exciting possibilities in the future, particularly in the use of nanorobots <a href="https://theconversation.com/nanotechnology-in-medicine-isnt-just-about-size-16054">in medicine</a>, that could be sent into the body to release targeted drugs or even <a href="https://theconversation.com/new-cancer-hunting-nano-robots-to-seek-and-destroy-tumours-30870">fight diseases such as cancer</a>.</p>
<p><a href="https://theconversation.com/five-ways-nanotechnology-is-securing-your-future-55254">Nanotechnology</a> deals with ultra-small objects equivalent to one billionth of a metre in size, which sounds an impossibly tiny scale at which to build machines. But size is relative to how close you are to an object. We can’t see things at the nanoscale with the naked eye, just as we can’t see the outer planets of the solar system. Yet if we zoom in – with a telescope for the planets or a powerful electron microscope for nano-objects – then we change the frame of reference and things look very different. </p>
<p>However, even after getting a closer look, we still can’t build machines at the nanoscale using conventional engineering tools. While regular machines, such as the internal combustion engines in most cars, operate according to the rules of physics laid out by Isaac Newton, things at the nanoscale follow the more complex laws of <a href="https://theconversation.com/explainer-quantum-physics-570">quantum mechanics</a>. So we need different tools that take into account the quantum world in order to manipulate atoms and molecules in a way that uses them as building blocks for nanomachines. Here are four more tiny machines that could have a big impact.</p>
<h2>Graphene engine for nanorobots</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=286&fit=crop&dpr=1 600w, https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=286&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=286&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=359&fit=crop&dpr=1 754w, https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=359&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/119480/original/image-20160420-25597-1nl4qwl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=359&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Graphene bulge.</span>
<span class="attribution"><span class="source">American Chemical Society</span></span>
</figcaption>
</figure>
<p>Researchers from Singapore have recently demonstrated a simple but <a href="http://phys.org/news/2014-05-one-nm-thick-graphene-mimics-two-stroke.html">nano-sized engine</a> made from a highly elastic piece of <a href="https://theconversation.com/harder-than-diamond-stronger-than-steel-super-conductor-graphenes-unreal-5123">graphene</a>. Graphene is a two-dimensional sheet of carbon atoms that has exceptional mechanical strength. Inserting some chlorine and fluorine molecules into the graphene lattice and firing a laser at it causes the sheet to expand. Rapidly turning the laser on and off makes the graphene pump back and forth like the piston in an internal combustion engine. </p>
<p>The <a href="http://phys.org/news/2014-05-one-nm-thick-graphene-mimics-two-stroke.html">researchers think</a> the graphene nano-engine could be used to power <a href="https://theconversation.com/swarms-of-robots-could-fight-cancer-with-your-help-17899">tiny robots</a>, for example to attack cancer cells in the body. Or it could be used in a so-called “<a href="https://theconversation.com/how-oversized-atoms-could-help-shrink-lab-on-a-chip-devices-43791">lab-on-a-chip</a>” – a device that shrinks the functions of a chemistry lab into tiny package that can be used for rapid blood tests, among other things.</p>
<h2>Frictionless nano-rotor</h2>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/119476/original/image-20160420-25612-1ios2u1.gif?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">
<figcaption>
<span class="caption">Molecular motor.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Synthetic_molecular_motor#/media/File:STM_rotor.gif">Palma, C.-A.; Kühne, D.; Klappenberger, F.; Barth, J.V. - Technische Universität München</a></span>
</figcaption>
</figure>
<p>The rotors that produce movement in machines such as aircraft engines and fans all usually suffer from friction, which limits their performance. Nanotechnology can be used to create a motor from a single molecule, which can rotate without any friction. Normal rotors interact with the air according to Newton’s laws as they spin round and so experience friction. But, at the nanoscale, molecular rotors follow quantum law, meaning they don’t interact with the air in the same way and so friction doesn’t affect their performance.</p>
<p>Nature has actually already shown us that molecular motors are possible. Certain proteins can travel along a surface using a rotating mechanism that create movement from chemical energy. These <a href="http://www.ncbi.nlm.nih.gov/books/NBK26888/">motor proteins</a> are what cause cells to contract and so are responsible for our muscle movements. </p>
<p>Researchers from Germany <a href="https://dx.doi.org/10.1073/pnas.1008991107">recently reported</a> creating a molecular rotor by placing moving molecules inside a tiny hexagonal hole known as a nanopore in a thin piece of silver. The position and movement of the molecules meant they began to rotate around the hole like a rotor. Again, this form of nano-engine could be used to power a tiny robot around the body.</p>
<h2>Controllable nano-rockets</h2>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/xMu1Ae4hYO8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>A rocket is the fastest man-made vehicle that can freely travel across the universe. <a href="https://www.newscientist.com/article/mg21128324-100-nanorockets-could-deliver-drugs-inside-the-body/">Several groups</a> <a href="http://phys.org/news/2012-01-bubble-propelled-microrockets-human-stomach.html">of researchers</a> have recently constructed a high-speed, remote-controlled nanoscale version of a rocket by combining nanoparticles with biological molecules.</p>
<p><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers">In one case</a>, the body of the rocket was made from a polystyrene bead covered in gold and chromium. This was attached to multiple “catalytic engine” molecules using strands of DNA. When placed in a solution of hydrogen peroxide, the engine molecules caused a chemical reaction that produced oxygen bubbles, forcing the rocket to move in the opposite direction. Shining a beam of ultra-violet light on one side of the rocket causes the DNA to break apart, detaching the engines and changing the rocket’s direction of travel. The researchers hope to develop the rocket so it can be used in any environment, for example to deliver drugs to a target area of the body.</p>
<h2>Magnetic nano-vehicles for carrying drugs</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=324&fit=crop&dpr=1 600w, https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=324&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=324&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=407&fit=crop&dpr=1 754w, https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=407&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/119354/original/image-20160419-13923-z1ga8b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=407&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Magnetic nanoparticles.</span>
<span class="attribution"><span class="source">Tapas Sen</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>My <a href="https://senlabs.org">own research group</a> is among those <a href="http://dx.doi.org/10.1063/1.4917264">working on</a> <a href="http://www.sciencedirect.com/science/article/pii/S0169409X1000133X">a simpler way</a> to carry drugs through the body that is already being explored with <a href="https://theconversation.com/lack-of-new-drugs-is-being-overcome-by-new-ways-of-delivering-old-ones-33109">magnetic nanoparticles</a>. Drugs are injected into a magnetic shell structure that can expand in the presence of heat or light. This means that, once inserted into the body, they can be guided to the target area using magnets and then activated to expand and release their drug.</p>
<p>The technology is also being studied for medical imaging. Creating the nanoparticles to gather in certain tissues and then scanning the body with a magnetic resonance imaging (MRI) could help <a href="http://hms.harvard.edu/news/magnetic-nanoparticles-predict-diabetes-onset-3-21-12">highlight problems such as diabetes</a>.</p><img src="https://counter.theconversation.com/content/58107/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tapas Sen receives funding from UK-India Educational and Research Initiative (UKIRI) and Royal Society. This article does not represent the views of the research councils or other public funding bodies.</span></em></p>A single-atom engine is the latest example of how nano-technology can create machines to power tiny robots inside the body.Tapas Sen, Reader in Nanomaterials Chemistry, University of Central LancashireLicensed as Creative Commons – attribution, no derivatives.