Nanotechnology

Seen by some as a transformative, almost revolutionary, set of technologies, nanotechnology represents a substantial investment of research dollars on the part of the U.S. government and many other governments around the world. While it has not received as much public attention as some might predict, nanotechnology has been the subject of an increasing number of news reports in recent years as its products begin to appear in the marketplace and knowledge of both its risks and its benefits grows. Part of the strategy for rolling out nanotechnology products in the United States, the United Kingdom, and elsewhere has involved a new emphasis on public communication and public engagement.

Nanotechnology can, however, be particularly difficult for nonspecialists to grasp. In short, the more that scientists and engineers can control matter at the atomic and molecular scale, the more power they have to shape our material world, whether in medicine, electronics, materials science, environmental science, or other areas.

While scientists and engineers have known a great deal about atoms and molecules for more than a century, a family of instruments called scanning probe microscopy, developed over the past 30 years, has greatly improved the ability to see the three-dimensional topography of atomic-scale surfaces, including molecules, proteins, and viruses. The scientific images produced by these instruments (especially the scanning tunneling microscope and the atomic force microscope) then make it possible to do extremely sophisticated before-and-after experiments, to see the results, and thus to learn to control matter at that scale.

Nanotechnology is the name for those activities. Nano is a scientific prefix meaning “one billionth.” A nanometer is one billionth of a meter (or 10–9 m in scientific notation), and from this scale we get the word nanotechnology, a collective term for several dozen related techniques that observe, manipulate, and manufacture matter that is measured at the scale of the nanometer. The diameter of a hydrogen atom, for example, is one tenth of a nanometer, and the water molecule (H2O) is approximately one third of a nanometer across. The DNA molecule is about 2 nanometers across, and the smallest viruses are roughly 15 nanometers. There is a well-accepted three-part definition of nanotechnology (also shortened to nanotech): It deals with matter that is 100 nanometers or less in at least one dimension; it takes advantage of forces like catalysis, magnetism, or conductivity, the effects of which are different at the nanoscale than at larger scales; and it generates material applications, which is a way of saying that it is not merely an exercise in scientific curiosity. While there are some limits to what nanotech can do because of certain intractable behaviors of atoms and molecules, this family of technologies nevertheless has great potential to affect almost everything material.