Medical Device Link.

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Exploring the hype

A common argument, particularly from some scientists, is that there is really no such thing as nanotechnology and that it is only “… what we have been doing for ages,” whether it is in physics, chemistry or biology. If this is the case, why is there all the hype and fuss about nanotechnology and the appearance of the “nano” prefix on almost everything from skin cream to personal electronic devices to stone cleaners? “Nano” now attracts huge amounts of money. For example, approximately €3.5 billion has been allocated for nanotechnology research under the European Union’s Framework Programme 7, with the unfortunate consequence that sometimes even mundane research is labelled “nano” to gain funding. Why has “nano” created almost unbridled excitement amongst some and deep scepticism in others? For clues we need to look back to the beginnings of this still fledgling area of technology.

When nanotechnology first came into the public eye in the mid 1980s, its first major proponent, Eric Drexler, laid out an ambitious futuristic scenario in his book, Engines of Creation.¹ This predicted universal assemblers that would be able to create “almost anything that the laws of nature allow to exist.” It is probably this statement that caused a lot of premature expectations. The book was an immediate hit and inspired many leading researchers to start investigating at the nanoscale while, at the same time, creating an immediate public interest in the new field of “nanotechnology.” The term was first coined by Professor Norio Taniguchi in his 1974 paper, “On the Basic Concept of “Nano-Technology.”² The excitement has remained and nanotechnology has thereafter been increasingly hyped up by many commentators.

Futuristic visions of nanomedicine do not only come from science fiction. Robert Freitas Jr., Senior Research Fellow at the Institute for Molecular Manufacturing (Palo Alto, California, USA) and author of the Nanomedicine series,³ is a leading proponent of the concept of medical nanorobotics. He published the first detailed prospective technical design study for a medical nanodevice, the “respirocyte,” in 1998⁴ and continues an exploration of the future possibilities for medical nanorobotics in this series of books. Although in the longer term this technology may become possible, currently science is at a much less complex stage of implementing medical solutions at the nanoscale. Yet, the image of the medical robot busily repairing cells in the bloodstream remains firmly in the public imagination.

A little caution

There is a balance to be struck here. Certainly, medicine at the nanoscale offers the prospect of new drug delivery systems, vastly improved imaging and diagnosis, huge strides in regenerative medicine, new generations of devices, and treatments for hitherto untreatable diseases. Hence all the funding that is being allocated to research. Yet, it is likely to be a gradual and incremental process across a number of converging disciplines. It perhaps culminates eventually in the much longer term in smart, multifunctional, microscopic devices of the type foreseen by Freitas and others, manufactured by “bottom-up” molecular assembly. However, will we achieve that eventual goal without some futuristic visions to inspire new generations of students, scientists and medical researchers? It is not wise to raise public expectations or fears by some of the more outlandish ideas of fiction, but it is valid to postulate on where the increased ability to engineer at that level may take society.

A clear definition

Returning to the original question of whether nanotechnology is something new or merely an extension of existing science and technology. It is both. Certainly, nanoscience and nanotechnology can be seen as the natural and logical extension to existing sciences. Chemistry and some aspects of physics have always involved nanoscale interactions, as has molecular biology, and practitioners of those sciences can justifiably claim to have always “done nanotechnology.”

But nanotechnology is more than that. It is defined in the British Standards Institution’s Publicly Available Standard 71 as the design, characterisation, production and application of structures, devices and systems by controlling shape and size at the nanoscale.”⁵ It is multidisciplinary and product focused by its very nature. Until recently it had been impossible to consistently apply the necessary tools and control at the nanoscale to manufacture more than simple materials and structures, and certainly not the range of products currently in development and envisioned for the future. Some products incorporating nanotechnology currently on the market are

• suture needles incorporating stainless steel nanocrystals (Sandvik AB, Sandviken, Sweden)
• nanodiamond-coated surgical blade (GfD, Ulm, Germany)
• superparamagnetic iron oxide (SPIO) nanoparticles for magnetic resonance imaging (Advanced Magnetics Inc., Cambridge, Massachusetts, USA)
• wound dressings incorporating nanocrystalline silver particles (Smith & Nephew, Hull, UK)

Some more advanced nanomedical products in development are

• nanoporous drug-eluting vascular stent coatings (MIV Therapeutics Inc., Vancouver, Canada)
• nanobubbles for ultrasonic imaging (ImaRxTherapeutics, Tucson, Arizona, USA)
• nanoshells for photothermal ablation cancer treatment (Nanospectra Biosciences Inc., Houston, Texas, USA)
• magnetic nanoparticles for cancer treatment (MagForce Nanotechnologies AG, Berlin, Germany).

Nanotechnology is a convenient term for this activity, but it is essentially the application of a greater degree of knowledge and more precise methodologies at a given size scale (typically 1–100 nm) in existing sciences in a highly multidisciplinary way.

Nanomedicine in particular is characterised by this convergence of different disciplines. The application of nanoscience and nanotechnology to imaging, diagnostics, regenerative medicine, advanced medical materials and drug delivery systems typically involves interfaces and interactions between biology and chemistry, physics, materials science and other fields. This is driven by the ever greater understanding of biochemical processes and the novel ways materials act at the nanoscale.

As this progresses at a pace, it is important not to forget the public’s perception. Mishandled issues such as mad cow disease, genetically modified organisms and contaminated blood have left the public’s trust in scientists and government institutions at a low ebb. Media accounts often ignore scientific fact and dwell on phantom risks. Yet, most people are able to take complex decisions about risks if they are sufficiently informed and perceive a benefit. As the science becomes more complex and “invisible” it is necessary to put a proportionately greater effort into communicating to the public about it, including informing them about benefits and risks, and engaging them in the processes that govern issues that will undoubtedly shape their lives in the not-so-distant future.