What is Nanotechnology?
Physicist Atul Kulkarni interviewed by Layne Hartsell
Interview conducted at Sungkyunkwan Advanced Institute for Nanotechnology, Suwon, South Korea — 2009
Atul Kulkarni is a physicist in nanotechnology related to optical engineering and instrumentation engineering and also a project scientist at Bio FD&C, New Songdo City, Incheon
Layne Hartsell is an assistant professor at the Sungkyunkwan Language Institute and an adjunct at Sungkyunkwan University College of Natural Sciences.
Layne Hartsell (LH): What is nanotechnology and its aspects?
Nanotechnology or, more specifically, that subset of nanotechnology known as “molecular manufacturing”- consists of manipulating matter on an atom-by-atom or molecule-by-molecule basis to attain desired configurations. This description, though simple, is wholly accurate; however, its simplicity conceals a great deal of complexity in both the application and implications of nanotechnology. To illustrate these complexities, it is worth going a bit further in explaining what nanotechnology is all about.
The first time the idea of nanotechnology was introduced was in 1959, when Richard Feynman, a physicist at Caltech, gave a talk called “There’s Plenty of Room at the Bottom.” Though he never explicitly mentioned “nanotechnology,” Feynman suggested that it will eventually be possible to precisely manipulate atoms and molecules. When K. Eric Drexler popularized the word ‘nanotechnology’ in the 1980’s, he was talking about building machines on the scale of molecules, a few nanometers wide — motors, robot arms, and even whole computers, far smaller than a cell. Drexler spent the next ten years describing and analyzing these incredible devices, and responding to accusations of science fiction. Meanwhile, mundane technology was developing the ability to build simple structures on a molecular scale. As nanotechnology became an accepted concept, the meaning of the word shifted to encompass the simpler kinds of nanometer-scale technology. Due to the publicity generated by both Drexler’s work, institute scientists from all over the world began to have a vested interest in the field of nanotechnology. Dr. Richard Smalley, for example, specifically said that he was a “fan of Eric” and that Engines of Creation influenced him to pursue nanotechnology. Much of the work being done today that carries the name ‘nanotechnology’ is not nanotechnology in the original meaning of the word. Nanotechnology, in its traditional sense, means building things from the bottom up, with atomic precision.
LH: Nanotechnology is in the basic stages, not yet a repeatable or stable science?
AK: Nanotechnology is a buzzword from the scientific community and the subject of many publications for over a decade. It has virtually unlimited future potential to produce and improve new and existing products. Although nanotechnology products are years away, is this a good thing, or bad?
LH: What are the implications for ethics?
AK: Is it an ethical problem, similar to nuclear energy with its good and bad points? Is it a threat to power electronics engineering and manufacturing as we know it? Is the “march of science” going too far? Will Nano-sciences shape future society and how will citizens benefit from it? This was the question put to scientists, policy makers and stakeholders. Finally, the emergence of new technologies could also potentially lead to a widening gap between those who can afford these applications to enhance their lives and those who cannot — a similar trend to the existing digital divide. ‘The key question therefore is how to benefit from nanotechnologies while limiting these risks?’
LH: Can you give some details of the science?
AK: Advances in scanning probe microscopy, electron microscopy and other analytical techniques helped to spur on science and technology based around manipulating matter at a near-atomic scale. At a very basic level, this enabled the structure of materials to be probed and explored; and new materials with nanostructure-dependent properties to be developed. Perhaps the best known of the ‘new’ nanomaterials was carbon nanotubes — discovered in the 1990s. Single-walled carbon nanotubes (SWCNT) are in essence a single sheet of graphite (graphene), wrapped into a tube ~1.5 nm in diameter. This unique atomic configuration leads to a material with an exceptionally high strength-to-weight ratio; that is an excellent thermal conductor; that is highly electrically conductive and yet, may be an insulator or semiconductor if the atomic configuration is marginally altered. Many other materials show unique properties that are dependent on their nanostructure. These range from size-specific fluorescence in semiconductors such as cadmuim selenide due to quantum confinement, altered optical properties in nanoscale TiO2 and a whole host of surface area and surface chemistry-dependent behaviours in a wide range of materials. But these are relatively simple nanomaterials.
Current research is leading to the development of more sophisticated and heterogeneous materials and devices — based on an increasing ability to engineer in functionality at the nanoscale. For instance, multicomponent nanoscale particles are being developed for cancer treatment that will have the ability to attach to diseased cells, enable their position to be tracked, and destroy the cell while leaving surrounding tissue intact when signaled to do so. Further out, there is interest in replicating biological functions with engineered molecules and systems. For example, researchers at Rice University in Houston have developed ‘nano-cars’ — four carbon-60 molecules (the wheels) connected by organic molecules (the chassis), that demonstrate directional motion on a surface. These are seen as proof-of-concept for ‘nanoscale transporters’, able to move materials around in a controlled manner at the nanoscale.
From this very brief overview, it should be clear that nanotechnology is a concept as diverse as it is nebulous. In many ways, nanotechnology more closely represents a way of thinking or doing things, than a discrete technology. And this makes it particularly difficult to discuss potential risks in general terms. It makes little sense to compare, for instance, the risk to health of an electron microscope (a nanotechnology-based tool) with the risk to health from free SWCNT (a nanotechnology material); or the environmental impact of nano-electronics printing equipment (a nanotechnology-based process) with unbound TiO2 nanoparticles.
Several observations indicate that all of society, not just scientists, needs to take nanotechnology seriously. First, there have been major scientific and technological advances in microscopy, material science, molecular-level manipulation, and scientific understanding at the borderline between classical and quantum physics. A biomolecular motor, made of inorganic nickel propellers and powered by an ATPase enzyme, was created over two years ago. In a major step toward downsizing electronic components, single-molecule transistors have been created. Nanoparticle research has generated products including a nanoparticle carrier able to cross the blood–brain barrier to deliver a chemotherapeutic for the treatment of brain tumours and gold nanoparticle probes that detect DNA from biological warfare agents such as anthrax. Second, evaluation of the field by prominent scientists leaves little doubt that NT is going to lead to a major revolution that is going to have a significant impact on society. Dr Richard Smalley, Nobel laureate in chemistry, believes that ‘the impact of nanotechnology on health, wealth, and the standard of living for people will be at least the equivalent of the combined influences of microelectronics, medical imaging, computer-aided engineering, and man-made polymers in this century’. Third, major industrial countries are incorporating nanotechnology in their innovation systems: they see this as an engine for wealth creation in the near future. As a result they have begun to invest heavily in research and development. Fourth, there are applications that are about to be introduced into the market. Nanomix, for example, intends to begin selling by the end of 2012 which is nanotube-based sensors for detecting gasoline vapours that will help protect refineries, chemical plants, and pipeline stations from leaks — these will be 10 times less expensive than current sensors, and can operate for a year on a watch battery.
LH: What are some of the perils of nanotechnology?
AK: For the safety of nanotechnology, it is incumbent upon us to examine ways to use advanced technologies to adapt to newly found natural threats at macro and nano scales. We need to summarize such threats; list technologies that may help us adapt to them, and then determine how risk assessment might be upgraded to evaluate such threats and responses. From the human standpoint, most people may not want to give their autonomy to machines. Unsafe new product failure may increase the possibility of regulation. The government [or concentrations of power] may stifle our ability to innovate and develop the next industrial revolution. Moreover, there are problems which may derail commercialization such as insufficient investment capital, intellectual property issues impeding commercialization progress, process scalability, high cost of processing, societal benefits of nano not yet recognized, and liability which can extend back to manufacturing processes.
LH: Thank-you Atul
AK: You’re welcome, Layne!
Photo: Nanotechnology, MIT http://bit.ly/1PHsszY
