Nanobiotechnology and the communications industry

One of the UK’s two flagship nanotechnology centres, the Interdisciplinary Research Collaboration in Bionanotechnology at Oxford University, was having its mid-term review yesterday; I was there in my role as a member of the external steering committee. One thing I learnt that had previously passed me by was that one of the largest industrial collaborations they have is not, as one might think, with a pharmaceutical or biomedical company, but with the Japanese telecoms company NTT.

The linkup was announced last October; the $2 million project is concentrated in the area of the study of the function of membrane proteins. Why would they be interested in this? Membrane proteins provide the mechanisms by which living cells sense their surroundings and communicate with the outside world. As the leader of the NTT side of the project, Dr Keiichi Torimitsu, is quoted as saying, “We are especially interested in this field because of the possibility of future applications in the area of human – electronic interfaces.”

Science and Public Affairs

The summer edition of Science and Public Affairs, a magazine published by the British Association for the Advancement of Science, has some interesting articles about the debate around the social implications of nanotechnology (when I looked the website hadn’t been updated to the latest edition, so I don’t know which of these articles will be available online).

There’s a group of three short pieces of reaction to the UK Government’s response to the Royal Society Report “Nanoscience and nanotechnologies: opportunities and uncertainties”, one from me, one from the ETC group’s Jim Thomas, and one from the Royal Society’s study’s chair, Ann Dowling. The first two of these will already be familiar to readers of Howard Lovy’s Nanobot (if I was a proper blogger I’d probably insert something here about the mainstream media struggling to keep up).

More timely is an article by Nick Pidgeon and Tee Rogers-Hayden comparing the way public engagement was handled in the debate about genetic modification with what’s been done with nanotechnology so far. Pidgeon and Rogers-Hayden are social scientists based at the University of East Anglia; Pidgeon was the social scientist member of the Royal Society panel and both were involved in evaluating the success or otherwise of GM Nation?, the large scale public engagement programme run by the UK government on the subject of agricultural biotechnology. They found a lot to criticise about GM Nation; the debate was held too late, with commercialisation imminent and public attitudes already polarised, and the participants weren’t representative of the population as a whole.

In the nanotechnology debate, some of these problems can be avoided – the process has been begun much earlier in the development cycle, and it is clear that public opinion is not yet polarised to anything like the degree seen with GM. But the upstream engagement we are beginning to see with nanotechnology will bring its own difficulties, precisely because some of the applications and implications of the technology are not yet clear, and because broader issues of a much more political nature (who controls technology? who benefits? who do we trust?) become more prominent.

But the article highlights an absolutely central issue with upstream engagement processes, that I’m currently spending a lot of time thinking about in the context of Nanojury UK (I should note that Pidgeon is on the steering committee of this project, and Rogers-Hayden has been observing a number of the sessions). This is the crucial role of information about the science. How can one ensure that the participants of the process have good quality information, while ensuring that the way the information is presented doesn’t introduce bias? The credibility of the process depends on all sides of the debate feeling that their views have been fairly represented, but there’s a danger that this will lead to potential conflicts between holders of fundamentally different views about the status of scientific expertise.

Why, one might ask, do we not simply issue the participants in these processes with a pack containing all the serious and well-considered documents that have been produced on nanotechnology, such as the Royal Society report? Quite apart from the important point that most of the population hasn’t learnt to love turgid chunks of text in the way that academics do, there’s a danger here of too much information. I was interested to read David Berube’s sceptical comments on a consensus conference held at Madison, Wisconsin earlier this year. My feeling on reading these conclusions is that the participants, presented with such eminently reasonable documents as the Royal Society report, simply agreed with them, as well they might do. I’d hope, though, that the real value of this kind of public deliberative process would come from the new and unexpected insights that people who haven’t been previously been deeply immersed in the debate might come up with.

A visit from Sir Harry Kroto

We’re having a visit today, here at the University of Sheffield, from Sir Harry Kroto. Sir Harry, who shared the 1996 Nobel Prize in chemistry with Robert Curl and Richard Smalley is a graduate of Sheffield University and is here to open a new multidisciplinary research building which is going to be named after him.

Sir Harry gave a public lecture about nanoscience, which was an impassioned statement of his belief that nanoscience and technology (which he believes to be essentially synonymous with chemistry) offers the only way towards achieving a sustainable way of life for the whole of the world’s population.

At Hay-on-Wye

I’ve just finished my talk on nanotechnology here at the Guardian Hay Festival; I was speaking to a nearly full tent, competing only with the sound of the Welsh rain beating on the canvas. There were plenty of questions and afterwards I signed a dozen or so copies of Soft Machines. I have to admit to being more than usually nervous; the audience here gives the impression of being absolutely the epitome of the stereotypical Guardian reader; liberal, left-leaning (this I infer from the wild applause and cheering from the tent in which Tony Benn was talking), and not, perhaps, naturally uncritical supporters of science and technology. They also seem to have implausibly well-behaved and bookish children. Nonetheless it seemed to go well and the comments afterwards were very appreciative, with one exception.

Hay-on-Wye is an odd sort of place at the best of times; a sleepy small market town on the border of England and Wales which by some quirk has become the centre of the UK’s second hand book trade, to support which there’s grown up an infrastructure of organic wholefood outlets, expensive, yet tasteful and understated, guest houses, and shops selling arts and crafts of all kinds. Some tensions result from this collision of the rural and metropolitan cultures; some of these are conveyed in Iain Sinclair’s novel Landor’s Tower, which like all his work manages to impart an unlikely seedy, dangerous glamour to the world of second-hand books. But none of this takes away from the beauty of the landscape here; it’s where the rich orchards and half-timbered houses of Herefordshire meet the harder hills and moors of Wales, with its scrawny sheep and struggling hill-farms. This liminal quality is reflected in the strange place-names, neither Welsh nor English – “Evenjobb”, “Burfa”, “the Begwns”, and a surprising number of places called “Worlds End”. The area has a deep personal resonance for me, because as a boy it’s the first place that I was let out into on my own for a few days without adult supervision. In 1975 a school-friend and I, both just turned 14, walked and camped from near Shrewsbury to Hay-on-Wye. At the time it felt to us like a bigger adventure than going to the Himalayas. The friend, Mark Miller, later became a mountaineer of some notoriety (there are some good anecdotes about him in Joe Simpson’s memoir “This Game of Ghosts”) before a tragically early death in the 1993 Katmandu air crash.

I’m veering into literature and autobiography, clearly intoxicated by my adventure past the “Artists only” sign into the famous Hay Festival Green Room. The people around me are undoubtedly famous authors and literary figures, but I’m too unworldly to recognise them. Time for me to pick up my payment (a case of champagne) and return to my usual rather less literary surroundings.

When buckyballs go quantum

It’s widely believed that, whereas the macroscopic world is governed by the intuitive and predictable rules of classical mechanics, the nanoscale world operates in an anarchy of quantum weirdness . I explained here why this view isn’t right; many changes in material behaviour at small scales have their origin in completely classical physics. But there’s another way of approaching this question, which is to ask what you would have to do to be able to see a nanoscale particle behaving in a quantum mechanical way. In fact, this needn’t be a thought experiment; Anton Zeilinger at the University of Vienna specialises in experiments about the foundations of quantum mechanics, and one of the themes of his research is in finding out how large an object he can persuade to behave quantum mechanically. In this context, the products of nanotechnology are large, not small, and among the biggest things he’s looked at are fullerene molecules – buckyballs. The results are described in this paper on the interference of C70 molecules.

What Zeilinger is looking for, as the signature of quantum mechanical behaviour, is interference. Quantum interference is that phenomenon which arises when the final position of a particle depends, not on the path it’s taken, but on all the paths it could have taken. Before the position of the particle is measured, the particle doesn’t exist at a single place and time; instead it exists in a quantum state which expresses all the places at which it could potentially be. But it isn’t just measurement which forces the particle (to anthropomorphise) to make up its mind where it is; if it collides with another particle or interacts with some other kind of atom, then this leads to the phenomenon known as decoherence, by which the quantum weirdness is lost and the particle behaves like a classical object. To avoid decoherence, and see quantum behaviour, Zeilinger’s group had to use diffuse beams of particles in a high vacuum environment. How good a vacuum do they need? By adding gas back into the vacuum chamber, they can systematically observe the quantum interference effect being washed out by collisions. The pressures at which the quantum effects vanish are around one billionth of atmospheric pressure. Now we can see why nanoscale objects like bucky-balls normally behave like classical objects, not quantum mechanical ones. The constant collisions with surrounding molecules completely wash out the quantum effects.

What, then, of nanoscale objects like quantum dots, whose special properties do result from quantum size effects? What’s quantum mechanical about a quantum dot isn’t the dot itself, it’s the electrons inside it. Actually, electrons always behave in a quantum mechanical way (explaining why this is so is a major part of solid state physics), but the size of the quantum dot affects the quantum mechanical states that the electrons can take up. The nanoscale particle that is the quantum dot itself, in spite of its name, remains resolutely classical in its behaviour.

Nanojury UK – the first week

A citizens jury on nanotechnology, sponsored by the IRC in Nanotechnology at the University of Cambridge, Greenpeace, and The Guardian newspaper, has got under way in earnest this week. I wrote here about its launch.

The jury is taking place in Halifax, a large industrial town in West Yorkshire. Names chosen at random from the electoral rolls were invited to apply to take part, and about 20 names from those who so applied were selected in a way that gives a group whose diversity is representative of their community. The jurors sign up for 20 two and a half hour evening sessions – two a week for ten weeks – so it’s a big commitment. The first 10 sessions are on a topic that the jurors themselves choose, and the remaining 10 sessions are about nanotechnology. Having spent five weeks talking about youth crime, they are working well together as a group and they understand the process pretty well.

Wednesday evening was spent in a general discussion about technologies and their impacts, both positive and negative, together with a very brief, scene-setting introduction to nanotechnology. The first proper witness session was held last night, on the theme of nanotechnology in medicine. The witness was Beatrice Leigh. Bea was formerly Head of New Technology for the drug company GlaxoSmithKline; she now runs her own (somewhat smaller) drug discovery company. I thought Bea did a great job, giving a very clear picture of why nano will be important in the pharmaceutical and biomedical industries (and, on the way, not being shy about the current shortcomings and difficulties of big pharma). After her half-hour long statement, the jurors spent some time by themselves formulating what they felt were the key questions, and then Bea and I did our best to answer them. This part of the evening provided clear proof that you don’t need expert knowledge to be able to ask penetrating questions.

Next week the jurors will get to see a rather different take on nanotech – next witness is Jim Thomas of the ETC group.

Intelligent yoghurt by 2025

Yesterday’s edition of the Observer contained the bizarre claim that we’ll soon be able to enhance the intelligence of bacteria by using molecular electronics. This came in an interview with Ian Pearson, who is always described as the resident futurologist of the British telecoms company BT. The claim is so odd that I wondered whether it was a misunderstanding on the part of the journalist, but it seems clear enough in this direct quote from Pearson:

“Whether we should be allowed to modify bacteria to assemble electronic circuitry and make themselves smart is already being researched.

‘We can already use DNA, for example, to make electronic circuits so it’s possible to think of a smart yoghurt some time after 2020 or 2025, where the yoghurt has got a whole stack of electronics in every single bacterium. You could have a conversation with your strawberry yogurt before you eat it.’ “

This is the kind of thing that puts satirists out of business.

Re-reading Feynman – Part 3

As I discussed in part 1 of this series, Richard Feynman’s lecture “There’s plenty of room at the bottom” is universally regarded as a foundational document for nanotechnology. As people argue about what nanotechnology is and might become, and different groups claim Feynman’s posthumous support for their particular vision, it’s worth looking closely at what the lecture actually said. In part 2 of this series, I looked at the first half of Feynman’s lecture, dealing with writing information on a very small scale, microscopy with better than atomic resolution, and the miniaturisation of computers. In the second part of the lecture, Feynman moved on to discuss the possibilities, first, of making ultra-small machines and ultimately of arranging matter on an atomic level.

  • Small machines
  • Feynman enters this subject by speculating about how one might make miniaturised computers. Why, he asks, can’t we simply make them in the same way as we make big ones? (Recall that at the time he was writing, computers filled rooms). Why can’t we just shrink a machine shop: “Why can’t we drill holes, cut things, solder things, stamp things out, mold different shapes all at an infinitesimal level?”

    The first problem Feynman identifies is the issue of tolerance – a piece of mechanical engineering, like a car, only works because its parts can be machined to a certain tolerance, which he guesses to be around 0.4 thousandths of an inch (this seems plausible for a 50’s American gas guzzler but I suspect that crucial components in modern cars do better than this). He argues that the ultimate limit on tolerance must derive from the inevitable graininess of atoms, and from this deduces that one can shrink mechanical engineering by a factor of about 4000. This implies that a one-centimeter component can be shrunk to about 2.5 microns. Other problems that come with scale include the fact Van der Waals forces become important, so everything sticks to everything else, and that we can’t use heat engines, because heat diffuses away too quickly. On the other hand, lubrication might get easier for the same reason. So we’ll need to do some things differently on small scales: “There will be several problems of this nature that we will have to be ready to design for”

    How are we going to make these devices? Feynman leaves the question open, but he makes one suggestion, recalling the remote handling devices people build to handle radioactive materials, levers that remotely operate mechanical hands: “Now, I want to build much the same device—a master-slave system which operates electrically. But I want the slaves to be made especially carefully by modern large-scale machinists so that they are one-fourth the scale of the “hands” that you ordinarily maneuver. So you have a scheme by which you can do things at one- quarter scale anyway—the little servo motors with little hands play with little nuts and bolts; they drill little holes; they are four times smaller.” And then you use the littler hands to make hands that are even smaller, and so on, until you have a set of machine tools at 1/4000th scale. The need to refine the accuracy of your machines at each stage of miniaturisation makes this, as Feynman concedes, “a very long and very difficult program. Perhaps you can figure a better way than that to get down to small scale more rapidly.”

    Reading this with the unfair benefit of hindsight, two things strike me. We do now have mechanical devices that operate on the length scales Feynman is envisioning here, upwards of a few microns. These micro-electromechanical systems (MEMS) are commercialised for example, in the accelerometers that activate car airbags. For an example of a company active in this field, take a look at Crossbow Technology. But the methods by which these MEMS devices are made very different to the scheme Feynman had in mind; just as in the case of computer miniaturisation it’s the planar processes of photolithography and etching that allow one to get down to this level of miniaturisation in a single step.

    Returning to Feynman’s idea of the master-slave system in which you input a large motion, and output a much smaller one, we do now have available such a device which can effectively get us not just to the microscale, but to the nanoscale, in a single step. The principle this depends on – the use of piezoelectricity to convert a voltage into a tiny change in dimensions of a particular type of crystal – was well known in 1960, and the material that proves to do the job best – the ceramic lead zirconium titanate (PZT) – had been on the market since 1952. I don’t know when or where the idea of using this material to make controlled, nanoscale motions was first developed, but between 1969 and 1972 David Tabor, at the Cavendish Laboratory in Cambridge, was using PZT for sub-nanometer positional control in the surface forces apparatus which he developed with his students Winterton and Israelachvili. Most famously, PZT nano-actuators were the basis for the scanning tunneling microscope, invented in 1981 by the Nobel laureates Binnig and Rohrer, and the atomic force microscope invented a few years later. As we’ll see, it’s this technology that has allowed the realisation of Feynman’s vision of atom-by-atom control.

    Why would you want to make all these tiny machines? Characteristically, the dominant motive for Feynman seems to be for fun, but he throws out one momentous suggestion, attributed to a friend: “it would be interesting in surgery if you could swallow the surgeon. You put the mechanical surgeon inside the blood vessel and it goes into the heart and “looks” around.” Thus the idea of the medical nanobot is launched, only a few years before achieving wide-screen fame in Fantastic Voyage.

  • Rearranging matter atom by atom
  • Here Feynman asks the ultimate question “What would happen if we could arrange the atoms one by one the way we want them?” The motivation for this is that we would be able to get materials with entirely new properties: “What would the properties of materials be if we could really arrange the atoms the way we want them? They would be very interesting to investigate theoretically. I can’t see exactly what would happen, but I can hardly doubt that when we have some control of the arrangement of things on a small scale we will get an enormously greater range of possible properties that substances can have, and of different things that we can do.”

    We do now have some idea of the possibilities that such control would offer. The first, easiest problem that Feynman poses is: “What could we do with layered structures with just the right layers?” The development of molecular beam epitaxy and chemical vapour deposition has made this possible, and just as Feynman anticipated the results have been spectacular. In effect, controlling the structure of compound semiconductors on the nanoscale – making semiconductor heterostructures allows one to create new materials with exactly the electronic properties you want, to make, for example, light emitting diodes and lasers with characteristics that would be unavailable from simple materials. Alferov and Kroemer won the Nobel Prize in Physics in 2000 (with Jack Kilby) for their work on heterostructure lasers. This work is gaining even more commercial importance with the discovery of a way of making blue heterostructure LEDs and lasers by Nakamura, opening the way for using light emitting diodes as a highly energy efficient light-source. Meanwhile new generations of quantum dot and quantum well lasers find uses in the optical communication systems that underly the workings of the internet. You can see an example of the kind of thing that’s been done in a number of labs around the world in this post about work done at Sheffield by my colleague Maurice Skolnick.

    This kind of semiconductor nanotechnology still doesn’t quite achieve atomic precision, though. This is Feynman’s ultimate goal: “The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. “. On this scale, Feynman forsees entirely new possibilities; “We can use, not just circuits, but some system involving the quantized energy levels, or the interactions of quantized spins, etc. We can use, not just circuits, but some system involving the quantized energy levels, or the interactions of quantized spins, etc. “ Some of these ideas are already being realised; quantum dots (even though they are made with slightly less than atomic precision) display quantised energy levels deriving from their size, and the manipulation of spins in such quantised systems is at the heart of the ideas of spintronics and may provide a way of realising quantum computing (another field which Feynman was the first to anticipate). Feynman points out another advantage of making this with atomic precision: the ability to make exact reproductions of the things we make: “But if your machine is only 100 atoms high, you only have to get it correct to one-half of one percent to make sure the other machine is exactly the same size—namely, 100 atoms high! “

    Don Eigler, of IBM, demonstrated the possibility of single atom manipulation in 1990 with this famous image of the letters IBM picked out in xenon atoms. Given this capability, what can one usefully do with it? Feynman suggests that it might prove a different route to doing chemistry: “But it is interesting that it would be, in principle, possible (I think) for a physicist to synthesize any chemical substance that the chemist writes down. Give the orders and the physicist synthesizes it. How? Put the atoms down where the chemist says, and so you make the substance. “ Progress towards this goal has been very slow, emphasising just how hard the Eigler experiments were. Philip Moriarty provided an excellent summary of what has been achieved in his correspondence with Chris Phoenix, available as a PDF here. Feynman himself anticipated that this wouldn’t be easy: “By the time I get my devices working, so that we can do it by physics, he will have figured out how to synthesize absolutely anything, so that this will really be useless.” Nonetheless, Feynman stresses the value of these developments for science: “The problems of chemistry and biology can be greatly helped if our ability to see what we are doing, and to do things on an atomic level, is ultimately developed—a development which I think cannot be avoided. “

    Now we’ve gone back to the original source to see what Feynman actually said, in my final installment, I’ll assess what validity there is to the various competing claims to the endorsement of Feynman for particular visions of nanotechnology.

    A nanotechnology citizens jury in the UK

    Nanojury UK, a new experiment in public engagement in nanotechnology, got its public launch today with an article in the Guardian newspaper (see also the opinion piece in today’s Guardian by Mark Welland, the Director of the Cambridge Nanoscience Centre). The idea of a citizens’ jury is that a group of more or less randomly chosen people are presented with expert evidence on some controversial issue, and having weighed up the evidence present a conclusion. What’s interesting about this jury is the diversity of the bodies that have come together to make it happen; it’s sponsored jointly by the IRC in Nanotechnology at the University of Cambridge, Greenpeace, and The Guardian newspaper. The steering committee includes representatives from the NGOs ETC and Green Alliance, UK Government and Research Councils, the nanobusiness world and academia, in addition to the main sponsors.

    Readers of Soft Machines got an early tip-off about this project. I’m chair of the Science Advisory Panel, and my role is to make sure that we find a wide and balanced range of witnesses, with different points of view, to make sure the views the jury forms are informed by authoritative and credible sources of information. There’s been a commitment from the government representative who sits on the steering group, Adrian Butt, that the output from the jury will be considered by the Nanotechnology Issues Dialogue Group, which is the body the UK government established to coordinate its response to the Royal Society report on nanotechnology. Naturally, how seriously they take the output will depend on how robust they judge the process to have been.

    I’ve already found the business of getting the thing off the ground fascinating, not least in the way in which people with very different views about nanotechnology have been able to work constructively together. The process itself begins next week, and will involve 10 evenings over the summer, with the findings being released in September. I’ll be reporting here on my experience of the process as it unfolds; the Guardian has a Nanojury website here, which includes background material and discussion boards.

    Here’s the press release.

    The quantum bridge of asses

    A good way of assessing whether a writer knows what they are talking about when it comes to nanotechnology is to look at what they say about quantum mechanics. There’s a very widespread view that what makes the nanoscale different to the macroscale is that, whereas the macroscale is ruled by classical mechanics, the nanoscale is ruled by quantum mechanics. The reality, as usual, is more complicated than this. It’s true that there are some very interesting quantum size effects that can be exploited in things like quantum dots and semiconductor heterostructures. But then lots of interesting materials and devices on the nanoscale aren’t ruled by quantum mechanics at all; for anything to do with mechanical properties, for example, nanoscale size effects have quite classical origins, and with the exception of photosynthesis almost nothing in bionanotechnology has anything to do with quantum mechanics. Conversely, there are some very common macroscopic phenomena that simply can’t be explained except in terms of quantum mechanics – the behaviour of electrical conductors and semiconductors, and the origins of magnetic materials, come immediately to mind.

    Here’s a fairly typical example of misleading writing about quantum effects: The ���novel properties and functions��� are derived from ���quantum physics��� effects that sometimes occur at the nanoscale, that are very different from the physical forces and properties we experience in our daily lives, and they are what make nanotechnology different from other really small stuff like proteins and other molecules. This is from NanoSavvy Journalism, an article by Nathan Tinker. Despite its seal of approval from David Berube, this is very misleading, as we can see if we look at his list of applications of nanotechnology and ask which depend on size-dependent quantum effects.

  • Nanotechnology is used in a wide array of electronics, magnetics and optoelectronics…
  • …right so far; the use of things like semiconductor heterostructures to make quantum wells certainly does depend on exploiting qm…

  • biomedical devices and pharmaceuticals
  • …here we are talking about systems with high surface to area ratios, self-assembled structures and tailoring the interactions with biological macromolecules like proteins, all of which has nothing at all to do with qm…

  • cosmetics…
  • …if we are talking liposomes, again we’re looking at self-assembly. To explain the transparency of nanoscale titania for sunscreen, we need the rather difficult, but entirely classical, theory of Mie scattering.

    The list goes on, but I think the point is made. All sorts of interesting and potentially useful things happen at the nanoscale, only a fraction of which depend on quantum mechanics.

    On the opposition side, the argument about the importance of quantum mechanical effects is pressed into service as a reason for anxiety; since everyone knows that quantum mechanics is mysterious and unpredictable, it must also be dangerous. I’ve commented before on the misguided use of this argument by ETC; here’s the Green Party member of the European Parliament, Caroline Lucas, writing in the Guardian: The commercial value of nanotech stems from the simple fact that the laws of physics don’t apply at the molecular level. Quantum physics kicks in, meaning the properties of materials change. This idea of the nanoscale as a lawless frontier in which anything can happen is rather attractive, but unfortunately quite untrue.

    Of course, the great attraction of quantum mechanics is all the fascinating, and usually entirely irrelevant, metaphysics that surrounds it. This provides a trap for otherwise well-informed business people to fall into, exposing themselves to the serious danger of ridicule from TNTlog, (whose author, besides being a businessman, has had the unfair advantage of having a good physics education).

    I know that it’s scientists who are to blame for this mess. Macroscopic=classical, nanoscale=quantum is such a simple and clear formula that it’s tempting for scientists communicating with the media and the public to use it even when they know it is not strictly true. But I think it’s now time to be a bit more accurate about the realities of nanoscale physics, even if this brings in a bit more complexity.