Nanotechnology is the buzzword of the moment. With its roots in Richard Feynman's famous 'There's plenty of room at the bottom' talk of 1959, nanotechnology has taken off as an almost catch-all term of everything that is hot in the physical sciences and at the intersection with the life and medical sciences. By very definition the term covers a vast raft of different materials from biological to compound semiconductor with enormously varied functionality and potential applications. But is
the reality likely to live up to the hype anytime in the near future?
Peter Dobson, professor of engineering at Oxford University and founder member of nano-based start-ups Oxonica and Oxford Biosensors, suggests that nanotechnology is "more evolutionary than revolutionary". At the start of his career in the 1960s, Dobson was already researching areas that would now fall under the auspices of 'nanoscience'. And it is interesting also to note that Oxonica was originally named 'Nanox', but was changed, in part at least, "to lose the dreaded 'nano' word" he says.
A handful of start-ups, including Oxonica, are already making progress and bringing 'nano' products to market. One of the crucial aspects for any start-up, says Dobson, is an "understanding of the market and where you can fit into the supply chain and add value." Oxonica has a dear area of expertise in wet chemistry fabrication routes for nanoparticles in the 3-200 nm range, in particular for II-IV and III-V materials such as CdSe, CdS, as well as metals such as Au and oxides such as TiO z. Using colloidal chemistry and organometallic routes, specifically sized nanoparticles, with the required functionality and surface properties, can be created.
It was a struggle to get enough funding to launch, but says Dobson, "while in an ideal world we might have gone for more money, the restriction on a single deliverable product and tight business plan could have brought failure to the entire venture." As it is, the small scale and flexibility of the company have allowed it to diversify into different fields - a crucial skill for start-ups to be able to respond to the vagaries of the market - as Oxonica found out with its first product. Despite the solution that its nanopartide phosphors offered for low voltage fiat pane[ field emission displays, big manufacturers had started to turn away from this technology to alternatives such as printable OLEDs. However, a fruitful collaboration with a biochemistry department colleague led to a nanopartic[e technolo~/for sunscreens. With the potential to be added to all cosmetics, the market could be huge. Next up, and also with a sizable end market in mind, is nanopartide additives for fuels to reduce particulate emissions and improve efficiency.
Another area ripe for nanoparticles - that is being actively pursued by Oxonica and other companies like Quantum DotCorporation - is 3-5 nm quantum dots for biotagging and labelling. Here nanoparticles with luminescent or adsorbing properties are functionalizad to bind with biological molecules for genomic research. This type of application is in marked contrast to the high volume, low cost additives for cosmetics and fuels.
Moving to bulk manufacture is an important issue for nanotechnology to address. As Dobson says, "scale-up can be a bit of a nightmare" where the production of nanoparticles is based around colloidal chemistry. What works in the lab in a beaker - an oft quoted benefit of nanotechnology - can be extremely problematic on a larger scale where uniformity of temperature and other conditions become hard to achieve. Addressing such issues is being pin-pointed by US research funding as a high priority, but how realistic is it to expect academia to deliver on this challenge? Despite the prominence of academic-industrial partnerships, shouldn't each also be encouraged to build on their own strengths rather than encroaching on the others'? Dobson feels that high-tech research-orientated start-ups have been far more successful than large-scale industry and academic partnerships.
The reality of nanoscience and technology may tum out to be somewhat less revolutionary in the near future than current impressions might indicate. While there may well be a quantum computer in the next few decades, nanoscience and technology will - and in some cases already is - having an impact on society, but as Dobson says =without people realizing that they are dealing with nanotechnology". The truth is that nanoparticles, in particular, will improve performance in a plethora of technologies - including applications in many 'ordinary' materials from textiles to sidewalks. What is aLso certain, says Dobson, is that when all the hype is gone, "the biggest benefit of nanotechnology, will have been the bringing together of scientists from different backgrounds and disciplines".