tag:theconversation.com,2011:/africa/topics/nanobot-1654/articlesNanobot – The Conversation2016-04-21T12:06:08Ztag: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">
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<span class="caption">Graphene bulge.</span>
<span class="attribution"><span class="source">American Chemical Society</span></span>
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<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>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/xMu1Ae4hYO8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<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.tag:theconversation.com,2011:article/552542016-03-22T11:23:55Z2016-03-22T11:23:55ZFive ways nanotechnology is securing your future<figure><img src="https://images.theconversation.com/files/115999/original/image-20160322-32283-1f9sla3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Hidden tools are making the world a safer place</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The past 70 years have seen the way we live and work transformed by two tiny inventions. The electronic transistor and the microchip are what make all modern electronics possible, and since their development in the 1940s they’ve been getting smaller. Today, one chip can contain as many as <a href="http://www.extremetech.com/extreme/187612-ibm-cracks-open-a-new-era-of-computing-with-brain-like-chip-4096-cores-1-million-neurons-5-4-billion-transistors">5 billion transistors</a>. If cars had followed the same development pathway, we would now be able to drive them at <a href="http://www.cyrrusanalytics.com/#!The-300000-MPH-Volkswagen/cudg/561206a00cf25fa7fe26bc95">300,000mph</a> and they would cost just £3 each. </p>
<p>But to keep this progress going we need to be able to create circuits on the extremely small, nanometre scale. A nanometre (nm) is one billionth of a metre and so this kind of engineering involves <a href="http://mashable.com/2013/05/01/ibm-atomic-movie/#mI9MdlKo9uq5">manipulating individual atoms</a>. We can do this, for example, by firing a <a href="http://www.sciencedirect.com/science/article/pii/S0169433200003524">beam of electrons</a> at a material, or by vaporising it and depositing the resulting gaseous atoms <a href="http://www.sciencedirect.com/science/article/pii/S1369702114001436">layer by layer</a> onto a base.</p>
<p>The real challenge is using such techniques reliably to manufacture working nanoscale devices. The physical properties of matter, such as its melting point, electrical conductivity and chemical reactivity, become very different at the nanoscale, so shrinking a device can <a href="http://www.nano.gov/nanotech-101/special">affect its performance</a>. If we can master this technology, however, then we have the opportunity to improve not just electronics but all sorts of areas of modern life.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=393&fit=crop&dpr=1 600w, https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=393&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=393&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=494&fit=crop&dpr=1 754w, https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=494&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/115989/original/image-20160322-32309-1gvd1se.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=494&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Medical nanobots.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>1. Doctors inside your body</h2>
<p>Wearable fitness technology means we can monitor our health by strapping gadgets to ourselves. There are even prototype electronic tattoos that can <a href="http://www.wired.com/2013/03/sensor-tattoos/">sense our vital signs</a>. But by scaling down this technology, we could go further by implanting or injecting tiny sensors inside our bodies. This would capture much more detailed information with less hassle to the patient, enabling doctors to personalise their treatment.</p>
<p>The possibilities are endless, ranging from monitoring inflammation and post-surgery recovery to more exotic applications whereby electronic devices actually interfere with our body’s signals for controlling organ function. Although these technologies might sound like a thing of the far future, multi-billion healthcare firms <a href="http://www.cnbc.com/2015/03/11/glaxosmithklines-big-bet-on-electroceuticals.html">such as GlaxoSmithKline</a> are already working on ways to develop so-called “electroceuticals”.</p>
<h2>2. Sensors, sensors, everywhere</h2>
<p>These sensors rely on newly-invented <a href="http://www.azonano.com/article.aspx?ArticleID=4152">nanomaterials and manufacturing techniques</a> to make them smaller, more complex and more energy efficient. For example, sensors with very fine features can now be printed in large quantities on flexible rolls of plastic at low cost. This opens up the possibility of placing sensors at lots of points over <a href="http://www.rh.gatech.edu/news/206881/wireless-smart-skin-sensors-could-provide-remote-monitoring-infrastructure">critical infrastructure</a> to constantly check that everything is running correctly. Bridges, aircraft and even nuclear power plants could benefit.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/115992/original/image-20160322-32323-xbcrq5.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">Worried about your hairline?</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<h2>3. Self-healing structures</h2>
<p>If cracks do appear then nanotechnology could play a further role. Changing the structure of materials at the nanoscale can give them some amazing properties – by giving them a texture <a href="http://edition.cnn.com/2013/01/17/tech/mobile/p2i-liquid-repellent-nano-coating/">that repels water</a>, for example. In the future, nanotechnology coatings or additives will even have the potential to allow materials to “heal” when damaged or worn. For example, dispersing nanoparticles throughout a material means that they can migrate to fill in any cracks that appear. This could produce self-healing materials for everything from <a href="http://phys.org/news/2006-02-nano-world-self-healing-material.html">aircraft cockpits to microelectronics</a>, preventing small fractures from turning into large, more problematic cracks.</p>
<h2>4. Making big data possible</h2>
<p>All these sensors will produce more information than we’ve ever had to deal with before – so we’ll need the technology to process it and <a href="http://www.forbes.com/sites/ciocentral/2012/07/05/best-practices-for-managing-big-data/#275083feef02">spot the patterns</a> that will alert us to problems. The same will be true if we want to use the “<a href="https://theconversation.com/explainer-what-is-big-data-13780">big data</a>” from traffic sensors to help <a href="https://theconversation.com/how-big-data-and-the-sims-are-helping-us-to-build-the-cities-of-the-future-47292">manage congestion</a> and prevent accidents, or <a href="https://theconversation.com/the-promise-and-perils-of-predictive-policing-based-on-big-data-48366">prevent crime</a> by using statistics to more effectively allocate police resources.</p>
<p>Here, nanotechnology is helping to create <a href="https://www.theengineer.co.uk/nanostructured-glass-used-for-high-density-5d-data-storage/">ultra-dense memory</a> that will allow us to store this wealth of data. But it’s also providing the inspiration for ultra-efficient algorithms for processing, encrypting and communicating data without compromising its reliability. Nature has several examples of big-data processes efficiently being performed in real-time by tiny structures, such as the parts of <a href="https://www.technologyreview.com/s/522476/thinking-in-silicon/">the eye and ear</a> that turn external signals into information for the brain. </p>
<p>Computer architectures <a href="http://blogs.scientificamerican.com/observations/brain-inspired-computing-reaches-a-new-milestone/">inspired by the brain</a> could also use energy more efficiently and so would struggle less with excess heat – one of the key problems with shrinking electronic devices further.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/115995/original/image-20160322-32283-1x11t7u.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">From nano tech to global warming.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<h2>5. Tackling climate change</h2>
<p>The fight against climate change means we need new ways to generate and use electricity, and nanotechnology is already playing a role. It has helped create <a href="https://theconversation.com/lithium-air-a-battery-breakthrough-explained-50027">batteries that can store more energy</a> for electric cars and has enabled <a href="http://www.nanowerk.com/nanotechnology-news/newsid=37903.php">solar panels to convert more sunlight into electricity</a>. </p>
<p>The common trick in both applications is to <a href="http://www.telegraph.co.uk/news/science/science-news/12174733/Smart-wallpaper-which-absorbs-light-could-help-power-home.html">use nanotexturing</a> or nanomaterials (for example nanowires or carbon nanotubes) that turn a flat surface into a three-dimensional one with a much greater surface area. This means that there is more space for the reactions that enable energy storage or generation to take place, so the devices operate more efficiently</p>
<p>In the future, nanotechnology could also enable objects to harvest energy from their environment. New nano-materials and concepts are currently being developed that show potential for producing <a href="http://www.nanowerk.com/spotlight/spotid=33308.php">energy from movement</a>, light, variations in temperature, glucose and other sources with high conversion efficiency.</p><img src="https://counter.theconversation.com/content/55254/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Themis Prodromakis receives funding from the Lloyds Register Foundation, the EPSRC and the EU Commission. </span></em></p>From tiny robotic doctors repairing your body to the latest climate change-tackling tools, nanotechnology is fighting an invisible battle on our behalf.Themis Prodromakis, Reader in Nanoelectronics, University of SouthamptonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/38212011-10-13T19:38:51Z2011-10-13T19:38:51ZShow us your (carbon nanotube artificial) muscles!<figure><img src="https://images.theconversation.com/files/4430/original/3104958433_400f1febeb_o.jpg?ixlib=rb-1.1.0&rect=0%2C56%2C1538%2C1314&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Is that a nano-bot in your guns, or are you just pleased to see me?</span> <span class="attribution"><span class="source">jcoterhals</span></span></figcaption></figure><p>The idea of doctors deploying miniscule robots in your body to diagnose and treat medical conditions is closer to reality today with the development of artificial muscles small and strong enough to push such tiny “nano-bots” along.</p>
<p>I know – it seems the stuff of science fiction. The image of nano-bots zipping through arteries in pursuit of nasty pathogens is an oft-used trope of the future courtesy of <a href="http://theconversation.com/explainer-nanotechnology-and-you-743">nanotechnology</a>. </p>
<p>But in this this week’s edition of <a href="http://www.sciencemag.org/content/early/recent">Science Express</a>, my colleagues and I from the University of Wollongong – with colleagues from the University of Texas, the University of British Columbia and Hanyang University – report on a new type of “artificial muscle” – the name used for materials that can change their shape in response to stimulus. </p>
<p>Such muscles are currently being developed as motors for all types of micro-machines with applications emerging in portable electronic devices.</p>
<h2>How hard can it be?</h2>
<p>Creating small machines that can propel themselves through fluids is a monumental challenge; indeed, producing mechanical movements of any kind is difficult in confined spaces. </p>
<p>Muscles are the most prominent “motor” in nature and can operate very successfully at the micro-scale: insects fly; fleas leap tall obstacles; ants carry heavy loads. </p>
<p>Our new type of artificial muscle produces a rotating action 1,000 times larger than previously known systems. The new type of torsional muscle is generated from a thin thread of twisted <a href="http://theconversation.com/dont-believe-the-hype-carbon-nanotubes-are-merely-extraordinary-321">carbon nanotubes</a> produced by our collaborators at the University of Texas. </p>
<p>To put this in perspective, the thread is ten times smaller in diameter than a human hair. When immersed in a liquid <a href="http://www.medterms.com/script/main/art.asp?articlekey=3215">electrolyte</a> and with a voltage applied, the carbon nanotube thread absorbs some of the surrounding liquid. As it swells, the untethered end of the twisted yarn starts to turn. </p>
<p>Our research team discovered the amount of rotation was about 2,500 degrees for each centimetre of thread length. On a per-weight basis, the carbon nanotube thread generates nearly as much power and torque as conventional electric motors. And by attaching a plastic paddle 1,000 times heavier than the thread, we demonstrated a simple mixer for fluids. </p>
<p>The twisted <a href="http://www.nobelprize.org/educational/medicine/dna_double_helix/readmore.html">helical structure</a> of the carbon nanotube yarn mimics the muscular structure that occurs in elephant trunks and octopus tentacles. </p>
<p>In these systems the helically-wound muscle fibres contract against an incompressible core (think of this as being like a balloon filled with water) and cause the trunk or tentacle to bend and rotate. </p>
<h2>A world of gain</h2>
<p>Our research team comprises labs from four countries. My colleague Gordon Wallace, also from the University of Wollongong, emphasises “the importance of international collaborative research in tackling complex multidiscipline problems”. </p>
<p>At Wollongong, we set about trying to understand the source of the rotation and test the performance limits. After a while we were able to generate very large and very fast rotations. </p>
<p>Meanwhile, other friends at the University of British Columbia in Vancouver discovered the carbon nanotube threads also shortened in length when a voltage was applied. </p>
<p>When the Canadian and Texan teams visited Wollongong, we put two and two together and realised the shortening and rotation were both a property of the helical twisted structure of the threads. </p>
<p>The mixer application was developed in collaboration with colleagues at Hanyang University in South Korea.</p>
<p>The upshot of this international effort? We believe that, with further improvements in performance, it may be possible to propel a micro or nano-bot with these fascinating materials.</p>
<p>Which means they could be coming to a vein near you some time soon.</p><img src="https://counter.theconversation.com/content/3821/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Geoff Spinks receives funding from the Australian Research Council through its Discovery Projects and Centre of Excellence in Electromaterials Science.</span></em></p>The idea of doctors deploying miniscule robots in your body to diagnose and treat medical conditions is closer to reality today with the development of artificial muscles small and strong enough to push…Geoff Spinks, Professor, Intelligent Polymer Research Institute, University of WollongongLicensed as Creative Commons – attribution, no derivatives.