It’s clear to most people that the term nanotechnology is almost impossibly broad, and that to be useful it needs to be broken up into subcategories. In the past I’ve distinguished between incremental nanotechnology, evolutionary nanotechnology and radical nanotechnology, on the basis of the degree of discontinuity with existing technologies. I’ve been thinking again about classifications, in the context of the EPSRC review of nanotechnology research in the UK; here one of the things we want to be able to do is to be able to classify the research that’s currently going on. In this way it will be easier to identify gaps and weaknesses. Here’s an attempt at providing such a classification. This is based partly on the classification that EPSRC developed last time it reviewed its nanotechnology portfolio, 5 years ago, and it also takes into account the discussion we had at our first meeting and a resulting draft from the EPSRC program manager, but I’ve re-ordered it in what I think is a logical way and tried to provide generic definitions for the sub-headings. Most pieces of research would, of course, fit into more than one category.
Enabling science and technology
1. Nanofabrication
Methods for making materials, devices and structures with dimensions less than 100 nm.
2. Nanocharacterisation and nanometrology
Novel techniques for characterisation, measurement and process control for dimensions less than 100 nm.
3. Nano-modelling
Theoretical and numerical techniques for predicting and understanding the behaviour of systems and processes with dimensions less than 100 nm.
4. Properties of nanomaterials
Size-dependent properties of materials that are structured on dimensions of 100 nm or below.
Devices, systems and machines
5. Bionanotechnology
The use of nanotechnology to study biological processes at the nanoscale, and the incorporation of nanoscale systems and devices of biological origin in synthetic structures.
6. Nanomedicine
The use of nanotechnology for diagnosing and treating injuries and disease.
7. Functional nanotechnology devices and machines
Nanoscale materials, systems and devices designed to carry out optical, electronic, mechanical and magnetic functions.
8. Extreme and molecular nanotechnology
Functional devices, systems and machines that operate at, and are addressable at, the level of a single molecule, a single atom, or a single electron.
Nanotechnology, the economy, and society
9. Nanomanufacturing
Issues associated with the commercial-scale production of nanomaterials, nanodevices and nanosystems.
10. Nanodesign
The interaction between individuals and society with nanotechnology. The design of products based on nanotechnology that meet human needs.
11. Nanotoxicology and the environment
Distinctive toxicological properties of nanoscaled materials; the behaviour of nanoscaled materials, structures and devices in the environment.
All comments gratefully received!
Not that my knowledge of the topic is extensive but seems an exhaustive classification, although as you point out there is quite a bit of overlap.
More importantly, it is an appreciated effort in a ‘field’ that lacks clear definitions.
Richard
Wonderful post as usual. This is an excellent classification.
Couple of points:
I think enabling technologies can easily be classified into modeling, characterization and fabrication (properties to me are a subset of modeling and characterization).
I am curious about your definition of nanodesign and the distinction between nanomanufacturing and nanodesign. I would think thats a rather grey area.
Hello Richard,
I hesitate to suggest this, but most observers would expect a nano-taxonomy to clarify whether colloid science is nanotechnology. Reading the above, it would seem to me that you are deliberately but subtly not excluding it. Am I correct? Your list of definitions would seem to satisfy both the nano-purists and the nano-pragmatists on this matter.
(For those that care about such things, I am a nano-pragmatist but I know that does not apply to all of my colleagues. To me a nano-pragmatist is someone who accepts L’Oreal’s long list of nano-patents as nanotechnology, not someone who thinks milk or ink is nanotech.)
Mark, indeed I do think that many elements from the Discipline Formerly Known as Colloid Science fit into this taxonomy (and this will be made clear when the sub-headings are put in). Self-assembling systems fall under (1), many aspects of colloidal dispersions fall under (4), and liposomal delivery systems will come under (6) and (7). I always try to satisfy everybody! The point about purists and pragmatists is that there is a continuum between the most incremental to the most radical; L’Oreal making a liposome from lecithin and putting some vitamin E in it is in one sense fairly mundane but there is a continuous path from that technology to making a synthetic cell.
Deepak, both are good points. In principle modelling and properties belong together (I’d separate both from nano-characterisation, as the latter is meant to concentrate on the techniques rather than what the techniques measure), and the reason they are separated is down to scientific sociology rather than anything fundamental. The people who do modelling form a community distinct from people with more general interests in nanoscale properties and for this reason get a category of their own. I don’t think this is a good thing, but it seems to be the way things are.
I’d be the first to admit that the distinction between nanomanufacturing and nanodesignis not yet completely clear. The notion I’m groping around, as it were, is the idea that design that’s centred on the human interface is a quite different discipline to the chemical engineering or production engineering that’s involved in scaling processes up to the industrial scale. In present day terms, it’s the difference between what Apple is good at and what Flextronics is good at. I’m sure that for nano to reach its full potential we’ll need people from an arts/design background to translate between what’s technically possible and what people really want and need.
Richard,
You bring forth an excellent point and one of my long standing frustrations as a modeler. I do not think that modelers forming a distinct community of their own is a good thing. Modeling is just another way of prediction and analysis and should be accessible to most scientists. I make a distinction between theorists and modelers. Modelers use theory, just like a spectroscopist does.
Although these 11 classes of NT are exhaustive I think they won’t help much in clarifying what NT is for the public. In communicating of what characterises NT your 3-fold classification is easier to grasp and remember.
On this occasion I would like to suggest a complementary classification based on hazards and risks I made in the German edition of MIT Technology Review in its November 2005 issue which could be helpful in nano-risk dialogues. The three are:
1. contained NT (embedded nanoparticles, analytical tools like scanning probe microscopes, nanoelectronics)
2a. unintentionally bioactive NT (mainly loose nanoparticles, due to spillage in production processes or end-of-life dissolution of nanomaterials)
2b. intentionally bioactive NT (most of bionanotechnology, nanomedicine)
3. disruptive NT (autonomous nanosystems – e.g. Drexler’s assembler if ever realized but also artifical viruses or bacteria as researched in synthetic biology)
As Switzerland and Germany are preparing for citizen panels on NT, too, this classification could structure what is talked about.
Niels, that’s a very fair point. Different classifications have different purposes, and I’ll certainly carry on using my original 3-fold classification in talking to the public. The classification here is really to help science administrators and policy makers, to try and put some precision in the otherwise meaningless statements that we see that country z is spending €x million on nanotechnology, when we don’t know whether that means clay-reinforced plastic car bumpers or molecular electronics. I see the value in your classification, too, particularly in situations where you want to put the human impact first. Thanks by the way for the tip-off to your interesting Technology Review article which I took a look at from your website.