Teleconference with Professor George Whitesides

This evidence was taken by teleconference at a meeting of the working group on January 16th 2004. For reasons of clarity, the evidence session was recorded and transcribed, and is presented here in its entirety. Due to intermittent technical difficulties, some portions of the conversations were inaudible, and are indicated in the text. This text has been sent to Prof. Whitesides for comment, and at the time of press no comments had been received.


GW George Whitesides
AD Ann Dowling
RO Ray Oliver
NP Nick Pidgeon
RW Roger Whatmore
MW Mark Welland
ST Saul Tendler
AWD Andrew Dunn

Please Note: [ ] denotes an inaudible word or phrase in the recording.

AD Okay, well, thank you very much. I would like first of all to hand you over to Mark Welland to kick off the questions.

GW Okay

MW George, it's Mark. You've got a list of questions I think that were sent by email?

GW I do. Let me see, hold on a sec……anyway let's continue while I'm looking….

MW Okay well I have two questions which are really related questions and the first is that we've all been following as part of the study and have been trying to understand the sort of debate about grey goo and molecular manufacturing as proposed by Drexler, so one of my questions to you is, is there such a thing as molecular manufacturing, and if so, what is it in its broadest sense?

GW Well as I understand Eric's view of this, that is to say systems that [095] at the atomic and molecular level. You know that you can do that externally with an [STM] and that level of movement has been demonstrated, although it is more complicated than it's made out to be. At the level of the assembler is the notion of a system that can pluck out of this from the environment and use them to make complex systems or you know more to make itself, I think that's out of the question.

MW On what basis is it out of the question?

GW A couple of bases, the first is that there's the kind of issue that Rick Smalley has talked about of the fact that when you are doing assembly you need to have the devices that pick things up and put them down, being small relative to these, commensurate in size with the things that are being picked up and put down, and that's a problem with atoms and a problem with molecules. The second thing is that particularly when you are working with atoms there is a real issue of the energy required to break bonds, the reactivity of the fragments that are produced and their reactivity towards the tweezers and the [109] the system is put out. The third thing is that there is no obvious way of getting power to a system of that kind. A fourth which is a very substantial problem is the issue of the instruction set. That is to say the amount of information that has to be stored in order to make such a system work is very much out of wack with the size of the object that one is thinking about. Even in a very efficient system, which is a cell. Cells are typically in the order of microns and of course operate by completely different [synthetic] principles. So, the idea of doing this on a nano scale just strikes me as being not a realisable one.

MW So as far as you are concerned there is no such thing in the future as molecular manufacturing?

GW Well I'm not quite sure that I know what molecular manufacturing is. I think there's no such thing as the assembler.

MW Right.

GW If you define for me what you mean by 'molecular manufacturing' I'm happy to comment on it, but I'm not….the phrase isn't very sure with me.

MW I think it's primarily as you have already alluded to, the Drexler concept of molecular manufacturing which you've answered, but we have had some indications from people that there is an alternative view which doesn't have to take into account self-replication, but is somehow a process of manufacturing [smart] and on a more complex molecule than on a small scale.

GW Well first you can make the case that there is a field called chemistry which actually puts things together very handsomely and one of the problems with the sort of Drexlerian view is that there are in fact very sophisticated nano machines, the cell is full of them. There are very good ways of assembling atoms in space in very large quantities with some nanometre per scale precision, that's called chemistry. The problem is the problem of looking at the Ford assembly line, imagining robots that work on the Ford assembly line and then trying to downscale those objects to things that are on the micron or the nanometre scale and for a variety of reasons it’s there that I think it fails. Eric has a little bit tried to I think subsume biology into his view of things, and I happen to be a great enthusiast of the idea that by looking at biology there are absolutely breathtaking examples of very small highly functional systems that work. And I think that is part of the charm of nano. Now if you want to call that molecular manufacturing and molecular manufacturing in that sense is superimposed in some way on biotechnology, then I don't think one can argue with that proof.

MW Okay, I think that's answered the questions that I had. Has anyone else got a comment before the next question?

GW There is one point that's probably worthwhile making there, and that is a lot of the concern with the grey goo, the idea of grey goo is not really around whether its one or other kind of machine, it's around the idea of self-replication. That I think is the key issue, that anything that is self-replicating based on picking up whatever it needs from the environment is in fact an interesting issue. Chemistry has of course been interested in self-replication for a long while, and there is so far as I know no example of self replicating systems in the sense that we are talking about here anywhere in chemistry, so we've got a long long way to go before we can get to sophisticated self-replicators.

MW Okay, thank you George.

AD Thank you very much. Saul do you want to come in next?

ST Yes, thank you. The next question which I submitted to a large extent has been covered, it was trying to delineate the difference between molecular self-assembly and self-replication, so I think that to a large extent we have covered that. Going on from that, if you look at nanotechnology in its broader sense what do you believe the benefits of those technologies will be to medicine and health?

GW I think there are a number of them Saul. Let's just walk through some of the characteristics that nano brings. Now what really happens with nano? Well things that are nanometre in scale for one thing are in the regime of sizes per quantum phenomenon become important. And it is my view, which I can't really presently substantiate with our data, but by intuition that if there is something that is truly, truly revolutionary about nanotechnology it's going to come from the exploitation of quantum phenomenon in some way. Now in fact we already again have things that display and show quantum phenomenon that are smaller than nanometre scale or [168] molecules and a coloured dye is a perfectly good example of quantum phenomenon operation, but I think there are new kinds of quantum phenomenon that may come from the nanometre scale thing. Then there are simply things that are small. And we already have examples of the applications of small things particularly in biomedicine in areas like magnetic resonance contrast agents. I think that the general issue of asking you know what benefits can come from particular bio-compatible solids in the nanometre scale is an idea that's just really beginning to sort of firm up as an idea itself, what happens when we make [177] or make magnetite or we make calcium phosphate or something like that and then what can you do with those kinds of things? I don't think we know right now but at least there is an example in the contrast [179] you know, which works well.

ST So in 5 to 10 years what sort of products would you envisage coming out from those ….

GW Diagnostics are certainly going to be one, that's already well in progress.

ST I didn't hear what you said, sorry…?

GW Diagnostics. Certainly a variety of those, contrast enhancement agents I think is pretty clear, I would make an argument for new material systems and we haven't talked about the materials aspect of nanotechnology but I think that will certainly be an important aspect of things. One of the areas of nanotech, actually one of the areas is medicine, which is clearly exploding is imaging. One of the issues in imaging is going to be very fast, signal processing and signal processing will be enormously helped by high speed processing, which will depend upon revolutionary nanotechnology, it may or may not have a revolutionary component to it, but certainly revolutionary nanotechnology is going to work. The idea of being able to engineer biocompatible materials with nanometre scale precision is an important and attractive idea. And then you know in the long term I think that the notion of being able to build a science, which the science is a component of biology, which focuses on [ordinals] and their function as opposed to the larger cells or the smaller molecules, you know, it's an area that's in progress but it's still at the stage of [196.

ST In general if you look at this vision it's quite different from your robots which are sent into the blood stream to cure disease, am I right in thinking that?

GW Yes, I think there is essentially no virtue to be found in the robot business that we a little bit mentioned. One is that well, one is that there is some basic problems with physics because when one gets things smaller than the impact of [209] motion on directed motion becomes overwhelming, you simply can't have something go somewhere then it becomes essentially physically impossible, so the idea of a submarine swimming runs into real problems with the physics of [206] motion, and it neglects the fact that in the closest thing that one has to nano-submarine, which is a lymphocyte, a lymphocyte doesn’t work that way [209] swim to its target, it does something with quite a different series of processes than on primarily surface range. And I think that to spend time on thinking about things like nano-robots and nano-submarines, big resources which would be much better spent on [213]

ST Okay thank you very much.

AD Thank you.

RW Can I ask a question please? This is Roger Whatmore here. I have a question which really relates to, I suppose it goes back a little bit to the molecular manufacturing question which is to do with the use of catalysts and enzymes. What potential do you think that nanotechnology has to offer there in terms of creating new catalysts and enzymes?

GW Well I think the idea of new enzymes that certainly is going to work. My instinct is that the way that it is going to be done is as it is done now which is to say to start with the instructions set in the DNA and to manipulate that, and so it's going to happen but I would call it biotechnology and not nanotechnology, at least in the sense of molecular manufacturing. And then the issue with….

RW Sorry, can I just interrupt you there?

GW Sure

RW I agree with you, that it's not molecular manufacturing in the Drexlerian sense, it is by creating artificial catalysts of enzymes in that way you are producing entities which will bring other entities together and in such a way that they will react efficiently.

GW Yes..

RW And if you are then using biotechnology to create those, is there any source for concern about that?

GW Well, yes I think you can argue that in principle in some ways of thinking about that there are reasons for being concerned. Again, I would phrase this as a biotechnology problem rather than a nanotechnology problem because this is a little bit a question of definition. But if you think about the problem for example of re-engineering a pathogen to make it a more pathogenic organism, the way that you would do that re-engineering is by changing proteins that are present in the pathogen and this is the ability to do this is a principle available in molecular biology and I think it is a subject that people are quite worried about who are concerned with for example the possible futures in biological weapons.

RW But do you think, I mean going sort of away from such, shall we say, obviously concern-making topics as biological warfare enzymes are widely used industrially, do you see that the use of new biotechnological techniques to re-engineer enzymes might nevertheless should be some cause for concern?

GW I think the place where there is not concern, but an issue that needs to be checked on a case-by-case basis is that when you change the amino acid sequence you in principle can change antigens so that when one starts thinking about large scale uses of new proteins, that is to say proteins with new sequences, you do have to pay attention to what we call OHSC concerns, occupational and health and safety concerns, but these systems do in fact get run through OHSC type considerations in the United States, and I am sure because they are new chemical [252] and they can be introduced into industrial practice, they have to be checked for safety. Now you can ask legitimately whether you are comfortable with the details of those safety checks, but these are new proteins in the sense that any protein that's extracted from a bacterium and you know soap powder is a new protein, so I think the same kinds of issues can apply there. I don't think there is a fundamentally new type for concern.

RW Right, but I mean just to go away from the issue of shall we say the social side and go back to the more technical side, do you see that the application of anything new that's coming along in the areas that we now call nanotechnology might provide a source for entirely new concepts in either organic catalysts or inorganic catalysts i.e. enzymes?

GW In the enzyme story I think the answer to that is that I do not. Now, the issue with inorganic catalysts the problem there is that there are I think broadly two classes of inorganic [or organic] catalysts, and one of the homogeneous ones uses organic [ligens] to engineer with great precision in the molecular environment around the catalytic site to give selectivity and things of that kind, and we have a process for developing those kinds of things well exemplified by the lots and lots of work that's done with homogeneous catalysis which doesn't involve any concepts that I would associate with nanotechnology.

RW Right…

GW Now the other source that is to say supported heterogeneous catalysts, the issue there is that I could imagine that I could build, I don't know, a cluster of metal atoms of a particular size and shape and I could imagine that I would be interested in knowing about the catalytic activity of that cluster of metal atoms relative to some other cluster of metal atoms, but I would probably do this….I can't think of this really, I can't think of a way of doing that using nanotechnology that would lead me to other than a few catalytic sites, so I regard this as something which at this point of this is very much an academic exercise. And as you know when you operate something like a cracking catalyst the catalyst [coke] you burn of the carbon, the catalyst disperses as an oxide, you reduce it, it re-aggregates in different ways, things are mobile across the surface so that the basic sort of fluidity of many heterogeneous catalysts is such that if you could build something it probably wouldn't stay in the form that you built it for a very long period of time and use. So I actually could be quite enthusiastic about arranged aggregates of atoms to begin to try to understand the physical and physical organic chemistry of heterogeneous [289], and new concepts might come of that, which could eventually be bodied longer than catalyst, I'm not quite sure technically I would be able to do it now.

RW Okay, but at least for the future there may be some potential in applying what we call the sort of new nanotechnological technique in heterogeneous catalysis studies?

GW Yes, I think that's true.

RW Thank you.

RO Could I come in here George and ask you a few questions? This is Ray Oliver from ICI.

GW Right…

RO And my job here is I am immersed just now in looking at opportunities and options in so-called nanoscience and technology for the chemical industry. And for my own company in particular. However, I am interested therefore in next generation manufacturing and I believe that next generation, or genuine nanomanufacturing is quite maybe a decade or more off yet, but I wonder in terms of the integral part to exploit small technology, could you comment on the use of techniques such as self-assembly and directed from methodologies to get towards [306] and reliable process technologies?

GW Yes, I mean I think there is an enormous range of interesting opportunities in this area, and you've touched on two issues. One is nano and one is self-assembly and there is an overlap between them, but also some differences between them, and let me just sort of touch on a couple of different subjects here. First, I would think that we are going to see some nanomanufactured products sooner than you know , whatever period you said…

RO A decade…

GW …I think it's 5 to 10 years, of course we already see some. Fume silica and fumed carbon are nano products, and you know I think we are on the verge of finding enough applications for bucky tubes primarily to enhance electrical conductivity that one will probably see some real industrial production of bucky tubes whether they are single or multi-wall tubes I don't have a very good sense right now. And I think that you know the stage, the properties of a number of these rod-like objects, either the sort of Chuck Martin type of things, what's the company, Nanoplex? Is that right?

RO Yes..

GW That makes those things, and I mean they are obviously doing a good job in beginning to learn how to manufacture them and their applications I think are mostly in bar coding, but you could also think of some of these as being dyes, the quantum dot type applications, that actually would be fairly optimistic that one would begin to see particular solids more or less structured beginning to enter especially the chemical industry as real products in less than 5 years.

RO I think that's interesting and I understand and we ourselves have manufactured a lot of nanopowders for a number of years, and I think I said at a meeting recently with the Working Group I think it's very much the trivial end of nano and I am much more interested in will we get to grips do you think with having organised structure? And would it be organised rather than disordered structure, are they valuable anyway in your opinion?

GW Yes, well, now, may I in fact entirely agree with the statement that you've just made, and if one begins to work one's way up, then you know, the next question is things like surface coatings, self-organising surface coatings. You've mentioned sands, and I think that sands are one such thing, you can make an argument for a multi-layer polymer electrolyte coatings other [344] sort, you know that kind of thing, those are at the border between chemistry and material science and nanotechnology and I think there's no question that those are useful and are going to continue to be useful. I mean after all oil floatation is basically self-assembled monolayers, and as we begin to learn more about them there will be a lot that can be done with them. I think that going beyond that there are a series of applications for example building ordered structures of colloidal spheres for optical applications or ordered plates for reflective surfaces, or you know you are familiar with many of these sorts of optical applications.

RO Yes…

GW And then I happen to be very enthusiastic about the long term potential of doing things like ultra precise positioning of parts in manufacturing [shadow ball] placement, placement of the control pixels [dry] pixels for large area displays, things where you are taking you know 1 to 100 micron pieces and you want to have a lot of them and you want to position them with high accuracy on some large sheet or interior surface or some place that's just not accessible using conventional manufacturing practices. I think that's a very attractive area. And then of course there's one other that you are very familiar with which is that to the extent that one can control the precision of things like injection moulded parts, you dramatically simplify the cost and increase the yield of things that you assemble from that, which is something that the Japanese have taught us to our distress in how to make consumer goods, and nanotechnology is going to come into that, both in terms of the metrology of those processes, being able simply to measure the kinds of things that one is interested in rapidly and economically, and also I think very much in many aspects, building the dies, understanding how to build composites in such a fashion that they end up being dimensionally stable with fine tolerances, all of the kinds of material sciences that come into that. Now, you know, is this material science, is it manufacturing science, is it nanotechnology? I think that to try to pick a part of this and say it's going to be all nanotechnology 100% is just not realistic. Almost all of these are going to require a systems integration of a range of technologies of which nanoscale components or nanofabricated components are going to be an important part. And just let me add just one last thing here which of course all of you are more than familiar with, but when one talks about an important nanotechnology to me the most important nanotechnology is already rapidly getting in place which is the evolutionary progress of the IT industry, the integrated chip manufacturers into dimensions which are below 100 nanometres. So I mean I have every expectation that we are going to see certainly nanometre design rules in the 10 year period. I don't know how far down that will go because that could get to be very, very expensive.

RO Yes, I'm interested in that comment George because of just [from] the chemical industry, I mean you realise that the 20/20 document came out in November…

GW Right…

RO Dealing with nano materials in the US, the same sort of thing is being looked at in Europe and no doubt in Asia Pacific, but can we learn a lot do you think in terms of the way that we look at future chemical [generic] future, in terms of semi-conductor technology and practice?

GW I think the answer to that is absolutely yes. And I saw a little note when I was…I just came back from Arizona and there was a note there that Intel I think had just upgraded their [Fab] Line to work with 300 millimetre wafers…

RO Right…

GW …and the cost of that upgrade, the cost of the upgrade not the fab but the upgrade was $2billion, and what this provides to me is an enormous economic driver for trying to simplify the fabrication of things with small dimensions. We have got things with small dimensions. I mean no doubt that we have them and we are going to have more of them and the whole trend in technology is to make things small for a lot of reasons, for portability, to decrease material costs, to decrease space consumption for a number of other reasons, but rather than reaching in from the outside with a robot or a beam of light and placing things that way, the notion of being able to let the pieces build themselves just makes enormous sense to me.

RO Right…..

GW And so I think even the electronics industry is beginning to be receptive to thinking about these sorts of ideas as methods of cutting or thinning down their capital and operating expenses.

AD Could I just come in there and ask if you see that as destabilising the markets a lot? I mean at the moment manufacture of chips is a high entry activity, you need a huge investment like Intel to have a state of the art production line. Would you see nanotechnology turning it into something that people do, not quite at the bottom of their garden, but that there would be a much easier entry level in emerging countries and economic environments?

GW My instinct in that is that this stuff, at least for the foreseeable future, and the foreseeable future being 10 years, that the fabrication of high end microprocessors and [427] type chips will remain a very complicated and sophisticated operation. So what one will see in some [429] is a decrease in the rate of increase of the cost of doing these things, rather than you know a completely different shift. However, having said that I think that there is a potentially revolutionary technology beginning to emerge now which is organic electronics, not molecular electronics that's a different thing, but organic electronics, meaning devices that have the characteristic that both the semi-conductor and perhaps the metal, the conducting components, will be made out of organic polymers, and those devices will be made by some combinations of printing resin, photo lithography, and they are going to have I would say modest performance, not high end performance. They are going to be just the kind of things you want for children's toys, and bar codes and simple displays and a whole range of products which we could consider low end or medium end products at this point, but they are going to come with the fundamentally different price point, and I think that that technology could well, you know, where that technology develops is a very, very interesting commercial point, because historically it's been difficult for companies who are like Intel, highly specialised in a high technology to get a grip on areas that are low technology, back to companies that are, I think, most advanced in that area are …a company that's making a big push in that direction is Philips and you know Philips is not a competitor with Intel for high end chips, but Philips is very good in consumer electronics. And so that poses a different vector, and I will say also that those are the kinds of technologies that, if I were in China or India I would be very interested in exploring, because I think there is an opportunity for countries that do not have enormous in place capital investment in these current technologies to get a foothold in an emergent market.

RO One last question and I'll leave this part of it George. Again, I was intrigued when you mentioned the idea of how you maybe change the paradigm because the chemical industry for instance would never contemplate plants at any other level, maybe they are far too expensive. So that means that this idea of manipulating materials say through external fields and therefore moving towards directed [funds] I think could be very challenging, but also very productive. So the chemicals and the processing and materials industries, how do you feel about that, in terms of these becoming possible potential desirable criteria using direct assembly?

GW Well, you know, I am sufficiently enthusiastic about this, a significant fraction of our research group works on it, so you are talking in this case to the converted. I think the opportunities are enormous there. Whether this has anything to do specifically with nano, you know, many of the components that are going to be put together are going to be small components, so I think that you know, the ideas of finding new technologies for making designed heterogeneous materials that are highly functional is exactly the right direction to go.

RO Okay thank you.

GW You know, I think it is going to pose some interesting problems for the chemical industry because the issue with that is, many of these things are never going to involve 109 pounds per year or something.

RO I think you are looking at 103 pounds per year, but what $106 per kilogram?

GW Ah, that's what the chemical industry has never been very good at doing.

RO Yes, and I think that's why it may have to change though, I mean I think it's them that have to change.

GW Yes, yes, that's where I agree with you.

RO Thank you.

AD Who wants to come in now?

RW Okay, shall I ask a question about…which is really number….this is Roger Whatmore here…which is on number 6, which is to do with your view of the public perceptions of nanotechnology, and how you think these ought to be addressed?

GW I think you know this is a really interesting subject. The nanotechnology is new and it's interesting and when it's new and interesting there will inevitably be concerns about it, and I think the public is actually….my impression is the public is more sophisticated that any one really gives it credit for. I don't think the public is easily spooked by things, but I think there are issues which come up that have a lot to do with making sure that people have the sense that they are a part of the process of the introduction of a new technology and will benefit from it. And I have a friend here, [512] who is in the science museum in Boston, who makes the point that a key issue is understanding ….offers the opinion that a key issue in introducing a new technology is the question of control. That is to say, who is choosing the time, place and manner of introduction of the technology and who will benefit from it? And one of the ways in which genetically modified organisms came a barrel of public opinion was in fact the pretty legitimate point that the public didn't see that they would benefit from this and they saw some potential for risk, I don't think people thought it was very great, but they thought there was some, but they didn't see much benefit, ….much potential for benefit, and so to me, the issues here are, the one thing to have a transparent so far is possible conversation about risk and benefit. People don't understand risk benefit very well as a concept, but they do understand that the cards are face up on the table, and I don't…I personally do not think that there are very many risks in nanotechnology, so I think it's a place where one can have these discussions without running into any of the really extremely interesting complicated ethical problems that come into for example advanced biology right now. And then the other issue is this question of ownership and benefit. You know, who is going to control these technologies? What is the process by which a new thing will be introduced and what form will it come? I just think we need to talk about these in public. So my sense is the public is not buffaloed by grey goo, these are interesting science fiction kinds of concepts and I don’t think people take them enormously seriously. But probably the best way of keeping things in that steady footing is to make sure that there are good public discussions and people can ask their questions and even the radical fringes have their day in the sun, and my general sense is that we don't have a serious problem here and I think that we can hope to prevent a serious problem from emerging by being more open and less sort of focussed on the annual term [560] for specific corporations and more focussed on the question of why this is beneficial and what the potential risks are. I think it is also important to ask, are there risks, and it’s worthwhile to look at particulate solids. I don't think that this is a major problem and it is a problem that comes up anyway. I mean the whole business of what we call in the States 'black carbon' which means small soot particles that come from fires, come from road grit, come from diesel exhausts, come from everywhere, I think one probably doesn’t want to begin to add to that large quantities of nanotubes or [005] solids, until one has some sense for what goes on. The general rule in toxicology is that very small particles and very large particles are not big problems. The very small particles because they tend not to lodge in the lungs, that is things that are you know 50 nanometres, and then things that are 100 microns tend not to lodge, but the size of the particle that really does get down into the alveoli is in the 1 to 5, 10 micron region, which is a little bit out of that size range, but I think it's fair to say that we don't know as much as we should about the toxicology of those kinds of small particles and again, this is to me you know it's not a high order risk because we know on the one hand that there are diseases like silicoses and black lung, and they are serious and we have to, insofar as we can, avoid introducing new ones of that sort in controlling the old ones. On the other hand we have all lived with diesel exhausts and burning wood fires for most of our lives and [016] but it's clear that those are not major causes of human mortality. So I think that taking just the kind of responsible care that the industrial system should take to look at these things carefully is a good thing to do and that may require a little bit of oversight because you want to make sure that companies that are in a hurry to get new products to market don't bypass anything.

RW So caution, but not alarm.

GW Caution but not alarm.

RW Yes, I mean following on from that, do you see any need for any new regulations or do you think these sorts of questions can be handled by the existing regulatory regimes that we have in the Western world?

GW My sense is that they can be handled by the existing kinds of things, the thing to remember in particulate solids is that the quantities of particulate solids produced by fires and by well, particularly internal combustion engines generally is so many orders of magnitude larger than anything that one can conceive of from nanotechnological manufacturing, that the focus is probably going to come from environmental issues rather than from nanotechnological issues, but I think that in the course of thinking about the toxicology of diesel exhausts and whether there should and shouldn't be regulations, I mean there are going to be regulations so what should they be? It would probably be efficient if one could try to look broadly at this class of small particulate solids at that time and ask, especially if there's anything unusual when you start making long thin tubes. An issue that for example has not, to the best of my knowledge been addressed, is that if you start embedding carbon nanotubes in a variety of things for improved electrical conductivity which I think is almost certainly going to happen, and the products of those [037] these are now polypropylene bumpers with nanotubes embedded in them, they start going into urban waste and perhaps there are fires through natural degradation, do they ever get out again? I mean I don't know that one, the other one my guess is that they are probably not, but, its something that could be looked at. The general supposition that at least I take with these is that when one has a very small particle, as soon as it comes in contact with anything else, you know, any microscopic solid surface, dirt, it tends to absorb and never re-suspends again. And so I think the lifetime of these things in the environment is finite, and it's not that you make them and they are going to accumulate forever, and so, understanding that cycle is still something that with nanoparticles, and in fact for a lot of organic materials we don't fully understand what goes on.

RW So I mean connected with that, but not quite the same thing is the issue of ethics in research, or ethics in application. Do you see any issues there?

GW At the moment the issues…I make the comparison, I think the issues in this area relative to those in advanced biology and some other areas are relatively minor. I look at the major issues with nanotechnology. Let me put this another way, what is my highest concern with nanotechnology? And it's a second order concern. I think nanotechnology as an enabling technology for information technology will enable…will be part of the system that enables the collection and storage of very, very large amounts of information about individuals, and this leads then to the concerns that everyone has raised about civil liberties and privacy and things of that kind. That's not specifically a nano concern in the sense do we want to engineer our children or do human performance [057] and things like that, and that concern is there regardless of whether there is a revolutionary nanotechnology or just evolutionary technology leading to more and more competent webs, and world wide webs and computers, and we know that that's going to happen, and it's going to happen for all kinds of reasons. So I see it as an issue to pay attention to in an ethical sense, but not specifically nano. So I actually am a big enthusiast of the idea of trying to get people to look at ethical and social issues related to new technology but so far nanotechnology strikes me as being of relatively low concern, relative to information technology and biotechnology.

NP Can I jump in there please? This is Nick Pidgeon from the University of East Anglia. And I mean if one looks further into the future though, I mean it's been suggested that the convergence of materials in IT and biosciences will mean that there may be other ethical problems out there, and I wonder if you've thought about that, or if you feel …because you used the phrase 'now' and I think that's a very good way to characterise certainly IT issue there, but is there anything further over the horizon that we ought to be thinking about?

GW Well there certainly are things over the horizon, and at what point that it becomes relevant to think about them is an interesting question.

NP Of course, yes…

GW When you start talking about machine hybrids, well, is that over the horizon? Yes, it's over the horizon but in practical fact we have all of these you know demonstrations of principle now in which one takes small not necessarily nano, but they could be nano, electrodes and implants them into the so-called brain of a cockroach and then you drive the cockroach in the same way that you….in a very clumsy way, but you can control the motion of the cockroach, let's put it that way. I think the process of going from there to higher animals is a long, long time, but that's the kind of thing that I think one does want to pay attention to, and when one puts together new technologies absolutely [080] to think about what their overlap might bring, because as you correctly point out, as information technology and biotechnology gets to be big, materials technology gets to be bigger and play a more important role in society their overlaps may bring some things that no field would necessarily think of explicitly. But, if you ask me do I see something right now that we are, you know, that I would worry about a lot that we are missing, I don't see it in the nano area right at the moment, so…

NP Okay thank you.

AD Okay is there anyone else that wants to come in with a question?

RO George, it's Ray Oliver again. I would be interested in your opinion about ….and because you've said it two or three times you know, a lot of these things are about small technology, how you put small things together to make functional materials which are beneficial and I know it may be micro….who knows….this idea of spending at the rate that the US government's spending like the last one, the last predict of 3.7billion over a 5 year period, do you think that's warranted?

GW I would make a couple of remarks about that. First, it is not that there are 3.7billion brand new dollars being spent on this.

RO It's old ones…

GW So you know, this is, I think one of ….that number represents an aggregation of a large number of things which fall in this general category of small and which in fact are, you know, this is a very important trend. And what I think people are beginning to realise, the shift that I would say in technology is this, that there is a period in which the idea of making things small was regarded as an exclusive interest of the electronics industry. I mean they made these amazing small things people thought and that was sort of it. Now you begin to realise that the idea of small, controlling small things and making small things, different kinds of functions, is actually an idea that's been out there in a wide variety of areas of science, for a long while, and it's a technology that hasn't had a name. It's been pervasive but it hasn't had a name. So, electronics and paint and [104] and yoghurt, and you know, you can go on, and on, and on, and add to these things like micro-fluiding systems which are new, new ways of building subways with optical materials like [106] resonant imaging and electrically conducted bumpers, and you look up and all of a sudden you find that the idea of small is actually a theme which is permeating a very wide range of technologies. And once that realisation comes then you I think sensibly, we, I think, sensibly, have said 'Ah Ha, there's something here that we hadn't thought about', and if we look at all of the aspects of small from biological machines, the surface chemistry of these things, quantum effects in small devices, nano-meteorology in manufacturing and all of the other things that you can imagine, that by looking at that and building a science and technology base we will be able to benefit a very large range of industries. So this is something which is not, let's build self-assembling robots because that's going to revolutionise the world, I don't think that makes any sense at all. But I think that the idea of understanding and controlling nature at scales in between those that we are familiar with, manufactured products bringing and those that we are familiar with chemistry producing, that intermediate scale of a few nanometres to you know, 100 nanometres, that this is a very important scale in nature, and it's one that has been much less explored at the level of fundamental science and applied technology than others, and hence represents an opportunity to do some really neat things.

RO Okay, I think that’s a very interesting approach in terms of shifting from electronics to essentially consumer goods, and materials. What about….I get asked this question quite often, what can nanoscience and technology do for food? And can that have wider implications especially in countries which are less well-off? But I think it's a difficult one.

GW Yes, I mean food for….sophisticated food is in fact as you well know highly dependent upon colloid science, so all issues of mouth feel and consistency and re allergy and things like this, these are all often phenomenon that depend upon heterogeneities of that scale, so I think that, you know, nano in those kinds of areas and also for flavour delivery and stuff of that sort is actually just exactly what I was talking about. It's part of the technology base for that industry, and certainly people who are in that industry are interested in the basic science for those kinds of reasons. The question of how does this help in the third world? I don't know the answer to that right now. It is certainly true that if you think about things like, let's take reverse osmosis membrane, I mean an oral membrane is a nanostructured object. A fuel cell membrane is a nanostructured object. And right now we make these objects because the membrane technologists have produced empirical recipes that make systems that are highly functional. If you ask me whether it would be possible to make things that are more functional by doing it on purpose using nanotechnology I think the answer is actually, yes it might be possible to do that, and there are, as you know, there are people who are beginning to think about, well, for example, metal filters that have genuine nanometre scale channels in them, but quite straight and quite short for use in things like food clarification, and lateral filtration with improved process economics than one can get using the using the current sort of anodising methods.

RO Yes..

GW So I mean I am actually pretty enthusiastic about that, but that will fall in the category of being technology which is transparent to the public, it will be important to the industry that actually uses it, but at the end of the day what the public is going to see is food that tastes the same as it tasted before.

RO Right, thank you.

AD Well, thank you very much Professor Whiteside for a very interesting conversation. Is there anything that we haven't asked you that you think we should have done? Is there a statement that you'd like to add?

GW Well, let me just add a couple of things which I think are important. One is that it came a little bit from the last part of our conversation, I'm an enthusiast of nano but I'm even more an enthusiast of the idea of small. And the issue here is that there are opportunities in making small systems over a wide range of things that are small, and you have to pick the right size for the right application and nano is not the answer to all questions. If I want to work for example in let's say microfluidic systems for cell base sensors for the pharmaceutical industry, then a cell is a 50 micron object and so it doesn’t really make any sense to talk about doing cell biology in nanometre scale channels, and it doesn't make a lot of sense to talk about doing optics and things that are 10 nanometres in scale, because the wavelength of visible light is what it is and at a certain point all you get is diffused scattering from nano to structured matter. So what one wants to do is to think about what can be done in a coherent overall science of small rather than a specific focus on nanotechnology that says 'this is the only thing to do in larger sizes or are now passé and no longer interesting', if anything I would say it's the other way around, but that there probably are more applications at the micron scale at this point than in the nanometre scale.

AD Do you think that's being appreciated sufficiently widely? Or do you think nano is running ahead in terms of funding?

GW I think that if you talk to people that are sophisticated in science and technology and science policy they understand this, but one of the issues with nano is that it's in a sense an iconic word. And if it's a word that is exciting to people and many people can't tell the difference between nano and micro it means a big difference to all of the rest of us but I think to the rest of the world nano just means very, very small and very, very small could just as well be micron, I don't see any [178] anyway. So, I don't terribly myself care what you call it, and nano sounds more exciting than small does so let's by all means call it nano if it works.

AD Right, was there another point you wanted to make?

GW No I think that's….well, one other point and that is that this is something that we've touched on but if one of the areas where I think there is a real opportunity convergence which has not yet been ceased is the intersection between biology and nanotechnology, and I don't know what's there yet, but every time I look at the operation of the chloroplast and mitochondria and DNA preliminaries and things I am simply blown away by the sophistication of those systems. I don't at the moment have any idea how I would take the principles that I see there and embed them in something new, but I do think that looking at nature and the way in which the cell and deflections of cells organise the business that they do on very small scales is scientifically going to be unbelievably interesting, and in due course I think out of that will come principles which in imaginative hands will lead to new ways of making nanometre scaled things. So as an area of basic science I think that getting the material scientists and the chemists and the biologists together and making sure that they are all telling one another of the neat things that they can do with [190].

AD Okay, well, thank you very much. Thank you for your time.

GW Okay, thank you all, good to talk to you.