Professor David Leigh and his colleagues from the University of Manchester, with funding from the European Union and the UK government, have designed a molecular machine, or nanorobot, with a ‘robotic arm’ that is able to pick up a molecular cargo, reposition it, set it down and release it at a second site approximately 2 nm (0.000002 mm) away from the starting position.
Before your molecular robots, how tiny was the tiniest robot in the world?
People have been making them out of DNA so those are also molecular robot, I guess, but they’re much bigger than our ones so they would be a factor of a thousand times bigger in terms of volume. And we’re making small molecular robot which only got maybe 150 atoms in them which is quite small and that’s the sort of thing that have been done with the DNA before.
That size allows you to be much more precise with the movement of components for example and then there are others differences as well with sort of DNA robots is that ours can work in different environment and DNA ones have to work in water or equivalent types of environment. So it gets that sort of differences like that. It depends of where it takes place. And also there are some advantages with the DNA systems, the DNA is very programmable because you can use the base that they use for programing the code. You can use that to program what you want the DNA robots to do whereas for us we have to design synthetics systems for doing that, which is more difficult.
How long have you been working on this project?
We are working on molecular machines for at least 15 or maybe 20 years but molecular robotics is to do with being able to manipulate substrates sort of mechanically and also to be able to program those movements into the molecular machines and so we’ve been working on trying to do that with the molecular machines, to take that full state of complexity for about the last five years and we published the first ones a few months ago. This is the latest robot, the one that can help to build molecules, that just comes out.
How does it take to build this kind of robot? Is it long?
To actually design it and then to find out how to assemble it, that would have taken us about 3 years to do. But now to repeat the synthesis that would take maybe 3 or 4 weeks to get. So I mean, most of the work is learning about how to design the systems and put them together. Once you’ve learned to do that, it is very reproducible.
Do you have a video of your molecular robot working with the microscope?
No yet. We woudn’t have it with the microscope anyway or with MFM or STM. These things are way too small to be seen with a microscope because they’re much smaller than the wavelength of light so you couldn’t do that.
It is with a specific machine, you can’t do that with a computer for example?
We can do computer modeling, we know exactly what the robot does because we can probe it using various sorts of instruments that will tell what the robot is doing. For example, one of the major instrument is something called nuclear magnetic resonance that you might be familiar with as IRM used in hospitals for scanners. That’s able to look at the environment of a particular atom and tell you exactly what those particular atoms are doing, so we use that to examine, along with other techniques, exactly what the robot is doing on each stage so I’m able to use computer modeling to keep us nice pictures but the actual data comes from those IRM images.
Because of the chemical reactions, can the robot only be handle by scientists?
At the moment yes but in principle, anyone could operate this operations if you’re just repeating the program and operations. That’s just injecting different solutions into the solutions of the robot in a solvent but eventually it will be possible to do this on surfaces as well, but in the moment it’s only our solution.
What kind of applications you can use your robot in?
The thing we are really exciting about, and that’s is what the robot is for, is that we hope to use, this is the first time this sort of molecular robot being use to manipulate molecular building blocks to build different new molecules by program it with chemical impulse, we can tell it to build different sort of molecules just like robots build cars on an assembly line in a factory. What we hope to do eventually is to have this sophisticated help that are able to build molecules in molecular factories. This will be great because maybe you can build pharmaceutical or you can build materials and if the molecular robots are doing it, that’s going to be much better in a long term that the way that it stands at the moment which is by scientists and chemists in pharmaceutical companies doing their mixing of chemicals in real factories, in chemical factories. That’s a long way of yet but that’s the ultimate goal.
It’s less dangerous/more secure?
Yes, it will be more secure, as always. I mean all technology over the past 60 years has been driven by the benefit of greater and greater miniaturization. So just after the second world war, first computers were the size of a room and they had less computing power than you have now in your smartphone where the computer is the size of a pinhead. It comes with great efficiencies in terms of materials, there’s less waste, less energy used, you require less materials to make useful things. We’re working in a very small scale and we’ll also be able to build things that we can’t build already and that’s very exciting possibilities that we got.
Can the robot assembly any kind of molecule?
Not yet. At the moment they can make only 4 molecules and there are billions and billions possible molecules. To make just four is nothing and to build this molecules, there are more efficient ways to do it at the moment than using a molecular robot but one day when the robot are more efficient we will be able to make more different things that’s when they will become useful. At the moment it is really really early days, all we’ve done is to be able to get 2 chemical reactions which make 4 different combines using the robot. But ultimately we will be able to program it and to make it build billions and billions of different things but that will take some times to do, a long time.
Maybe we could use them for curing?
Other people are already working on using molecular machines to chase cancer cells to kill them. So maybe these sort of things will be possible. At the moment, molecular robot that build things and cure cancer are science fiction but what we’re starting to know is that science fiction can become fact. It takes some time, it’s not gonna happen tomorrow but we’re making progress towards things that are science fictions, the very first step has been made.
Private or public organizations you’re discussing with to develop the robot?
At the moment, the research is done in university and is founded by the European Union and the British government but it’s too early technology yet for private companies because we’re talking about realistically to have molecular robots that can do better than humans, will be at least 10-15 years. But it’s going to happen.
Can be useful for pollution detection/environment?
Again maybe it will come in the future. I think the advantages of factoring molecules will be far less waste, because if you build things that small scale, you need far less materials so it will be definitely environmentally friendly, it’s the ultimate environmentally friendly sort of systems but it’s way too early to worry about that from the point of view of the scientist design because we have to make them work anyway we can. And it’s going to be a matter of developing. As soon as we can do things that we cannot do in another way that’s when they become economically exciting. At the moment they only can do very simple things that scientists can do or that we can do by ourselves just to bring together chemicals in a flask to carry out this chemical reaction. But what we hope is that the robot will be able to quite quickly do things we cannot do in another way and that will be the point to when they become economically important because as soon as you can do things more efficiently with molecular robots or do things that they can do and can’t in another way, as long as that application is financially significant then you have an economic imperative for making this sort of things. But we are just at the start.
Why was you interested by the subject at the start?
I was already interested in molecular machines so robotics and programming molecular machines comes naturally and the evolution of our interest in molecular machines, 20 years ago because we could see that this was the ultimate in miniaturization of machines, you cannot get smaller than molecules for performing tasks. All of advanced technology have come from miniaturization of components, not just computers, if you look your smartphone, the pieces are much more smaller than the handset that you have 20-30 years ago, battery technology, all of this things. The ultimate in miniaturization of machines is molecular machines and the ultimate miniaturization of robotics is molecular robot so we can see that we have reach the typing point where robots really are in reality and doing useful things and they are becoming more and more important. So molecular robotics will do things that we cannot do at the moment and they will do things more efficiently, even the things that we can at the moment, it will be more efficient, less waste, and do it more reproducibly and better. But what’s more exciting is that they will do things that we cannot currently do. And I think it is the same for big robot, you can use robots on factories in line to replace workers to do things you can already do, even robots can build cars. We can build robots so much cheaper, so much reliably, more advanced, more reproducibly, with less energy and do things that it’s not possible to do with humans at all.