[{"command":"settings","settings":{"ajaxPageState":{"theme":"hm_theme","theme_token":"E34nKtLDjtKr2ppDDJe9KxCTR5dbPVdXiX6vW9mRXEw","libraries":"eJwDAAAAAAE"},"ajaxTrustedUrl":{"form_action_p_pvdeGsVG5zNF_XLGPTvYSKCf43t8qZYSwcfZl2uzM":true},"pluralDelimiter":"\u0003","user":{"uid":0,"permissionsHash":"2af85631393b514cbde3779a1f71d92618d53b94b54ea1960d28b2e2d121ff12"}},"merge":true},{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/7417\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003EHow chemists are building molecular assembly lines\u003C\/h2\u003E\u003Cp\u003EIn 2016, three pioneers of building molecular machines were recognised with a \u003Ca href=\u0022https:\/\/www.nobelprize.org\/prizes\/chemistry\/2016\/press-release\/\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003ENobel prize\u003C\/a\u003E. Their work broke new ground. But the first tranche of molecular machines that they were rewarded for creating were mostly simple affairs such as rotors, switches and the like. Now chemists like Professor David Leigh at the University of Manchester, UK, are trying to build sophisticated molecular machines with several components and that can do useful jobs.\u003C\/p\u003E\n\n\u003Cp\u003EBuilding a molecular machine is a job for elite chemists but the basic tricks of the trade are easy enough to grasp. Some of them involve building molecules that are mechanically linked to one another. For instance, you might build a rotaxane, a ring-like molecule threaded onto a shaft. If you place different groups of atoms along the shaft and then manipulate their properties \u2013 perhaps giving and taking away an electrostatic charge \u2013 you can get the ring to move along the shaft. This is the kind of simple component that could be used in a more elaborate molecular machine.\u003C\/p\u003E\n\n\u003Cp\u003E\u003Cstrong\u003EBiochemical factory\u003C\/strong\u003E\u003C\/p\u003E\n\n\u003Cp\u003EWhat kind of things might we do with a more advanced molecular machine \u2013 or \u2018nanobot\u2019, as some call them? Prof. Leigh is particularly interested in building nanobots that act like a chemical assembly line, synthesising new chemicals with interesting properties. He\u2019s inspired by the ribosome, a biochemical factory in cells that builds proteins. It takes simple building blocks called amino acids, which come in just 20 different natural varieties, and stitches them together into long chains or polymers. Depending on the sequence of amino acids, those chains fold themselves up into an amazing array of different biomaterials \u2013 from the keratin that makes up our skin and hair to the fibres of our muscles.\u003C\/p\u003E\n\n\u003Cp\u003EChemists have made an amazing array of artificial polymers but it is extremely difficult to control the order in which the building blocks are joined together. \u2018Sequence specific polymers is an unsolved challenge in chemistry,\u2019 said Prof. Leigh. But he thinks molecular machines could be a solution. If we had molecular machines that could assemble polymers they wouldn\u2019t be limited to just the 20 amino acid building blocks nature has \u2013 so they might make an even more wondrous array of materials.\u003C\/p\u003E\n\n\u003Cp\u003EAchieving machines that can make sequence-specific polymers is far from trivial, says chemist \u003Ca href=\u0022http:\/\/www.katsonis.eu\/\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003EProfessor Nathalie Katsonis\u003C\/a\u003E at the University of Groningen in the Netherlands. \u2018But I am convinced that this research will play a big part in (the) future of chemistry, and possibly of materials science too.\u2019\u003C\/p\u003E\n\n\u003Cp\u003EProf. Leigh has been chasing this goal through his \u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/id\/339019\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003EMOLFACTORY project\u003C\/a\u003E, which began in 2014. In a key paper in 2017, Prof. Leigh and his team showed they could \u003Ca href=\u0022doi:10.1038\/nature23677\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003Ebuild a molecular robot arm\u003C\/a\u003E, a simplified \u2013 and much, much smaller \u2013 version of the ones that put cars together. This arm grabs hold of one reactive chemical and moves it to one of two sites. Depending on which site it is positioned at, the chemical reacts in different ways, to produce different chemical products. Developed further, machines like this could produce sequence specific polymers akin to the proteins produced by ribosomes. And just as different proteins can generate force (muscle) or be five times stronger than steel (spider silk), that might allow us to do similar things with artificial polymers such as a \u2018sequence specific polystyrene\u2019.\u003C\/p\u003E\n\n\u003Cp\u003E\u2018David and his group are doing phenomenally creative work,\u2019 said Professor \u003Ca href=\u0022https:\/\/physics.umaine.edu\/r-dean-astumian\/\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003ERaymond Astumian\u003C\/a\u003E at the University of Maine in Orono, US. \u2018Not only are the molecular machines they make of potential practical use, but they are also directed toward answering fundamental questions.\u2019\u003C\/p\u003E\n\n\u003Cp\u003EAnother project, called \u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/id\/837339\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003EProgNanoRobot\u003C\/a\u003E, led by Dr Germ\u00e1n Zango working in Prof. Leigh\u2019s laboratory, tried to take this production robot further. The project had a number of objectives, including producing robotic arms that could run on a chemical fuel; and a nano device capable of transporting molecular cargo over long distances (on the atomic scale, that is).\u003C\/p\u003E\n\n\u003Cp\u003EThe project ran between 2019 and March 2021 and as yet no results are published. But Dr Zango had some key successes. He said he produced a device in which a molecular cargo could be produced from one robotic arm to another, meeting that goal of being able to transport over long distances.\u003C\/p\u003E\n\n\u003Cp\u003EWorking on research \u2018that could lead us towards the dawn of useful molecular nanotechnology was at the same time an enormous challenge and a thrilling experience\u2019, said Dr Zango.\u003C\/p\u003E\n\n\u003Cp\u003E\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003E\u2018I really do think that eventually molecular machines will revolutionise things in the way the industrial revolution or the internet did.\u2019\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EProf. David Leigh, University of Manchester, UK\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\n\n\u003Cp\u003E\u003Cstrong\u003ETriggers\u003C\/strong\u003E\u003C\/p\u003E\n\n\u003Cp\u003EIn the near future, there are several big challenges that nanobot research needs to overcome. At the moment, it is often the case that molecular machines need to be fed a number of chemical triggers in a particular series to get them to work. If the systems were to be used to produce polymers at scale it would produce a lot of waste. Part of Dr Zango\u2019s work investigated reducing the number of chemical triggers needed or using light as a trigger instead. \u2018One of the most challenging things we were trying to achieve was to use a single chemical input to fuel a whole operating cycle of the machine or to use only photoswitches,\u2019 said Dr Zango.\u003C\/p\u003E\n\n\u003Cp\u003EAnother huge challenge, says Prof. Leigh, is error correction. Machines at the nanoscale are distinctly unlike human-scale robots in that they are always subject to stochasticity; you can set up a molecular machine to do a particular job but you can never ensure it will work correctly all the time. Biology has to grapple with this problem too. In our bodies, there is one set of molecular machines that build biomolecules \u2013 and another whole set with the specific job of finding and correcting the errors made by the first set. Prof. Leigh says that at some point artificial molecular machines will have to have some kind of error correction mechanisms. That kind of work is still in its infancy.\u003C\/p\u003E\n\n\u003Cp\u003EStill, in October 2020, Prof. Leigh and his team took a significant step towards building a sequence-specific polymer synthesiser. They \u003Ca href=\u0022https:\/\/www.cell.com\/chem\/fulltext\/S2451-9294(20)30485-X\u0022 rel=\u0022noopener noreferrer\u0022 target=\u0022_blank\u0022\u003Ebuilt a rotaxane-based robot in which a ring \u2018walks\u2019 down a track, picking up molecules along the way and joining them together\u003C\/a\u003E. The results only joined four molecules together \u2013 a far cry from the hundreds or thousands in a protein \u2013 but it was a big step nonetheless.\u003C\/p\u003E\n\n\u003Cp\u003EProf. Leigh said that there can sometimes appear to be hype about what molecular machines can do. But he reckons it will be justified in the long term. \u2018I really do think that eventually molecular machines will revolutionise things in the way the industrial revolution or the internet did,\u2019 he said. But it\u2019s definitely going to take time, Prof. Leigh adds.\u003C\/p\u003E\n\n\u003Cp\u003EHe admits there\u2019s nothing he can yet do with a molecular machine that can\u2019t be done more simply by other means. But when you\u2019re inventing something new that is somewhat to be expected. \u2018It\u2019s very much like stone age man making a wheel to grind corn,\u2019 said Prof. Leigh. \u2018He doesn\u2019t know that one day it will be used to make a car.\u2019\u003C\/p\u003E\n\n\u003Cp\u003E\u003Cem\u003EThe research in this article was funded by the EU. If you liked this article, please consider sharing it on social media.\u003C\/em\u003E\u003C\/p\u003E\n\n\u003Cp\u003E\u003Cem\u003EThe article was originally published on\u0026nbsp;17 May 2021.\u003C\/em\u003E\u003C\/p\u003E\n\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-8xd6-dsmslnzjytgh5cupgaqha7h-yw8x21-ahzqaig\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-8Xd6_dSmSlNZJyTGH5CupGaQha7h_yW8X21_aHZqAIg\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]