Ten Things You Should Know About Nanotechnology

Let's start with the basics: Nano comes from the Greek word for dwarf. The prefix nano means a factor of one billionth (10^-9) in the metric system and can be applied to time (nanosecond), volume (nanoliter), weight (nanogram) or length (nanometer, abbreviated as nm).

But why 100 nm as the upper boundary? This is roughly the scale at which quantum mechanical effects become significant, and materials begin to exhibit properties that differ from their bulk counterparts. It's not an arbitrary cutoff; it's where the physics changes.

It's genuinely difficult to imagine how small a nanometer really is. If you line up 7 oxygen atoms or 3 to 4 water molecules, you'll get about one nanometer. Still hard to picture? A red blood cell is approximately 7,000 nm wide. A single hair from your head is about 50,000 to 100,000 nm thick.

Another way to think about it: precisely positioning a one nanometer sized structure within a one meter line is analogous to positioning a peppercorn somewhere in the distance between New York and Miami.

We've devoted a Spotlight to this issue of perception: "Shaking hands with a virus: getting all touchy-feely with nanotechnology".

Often thrown together, we need to differentiate between science and technology:

Nanotechnology should really be called nanotechnologies: The term broadly refers to fields such as biology, physics, chemistry, or any combination thereof, that deal with the deliberate and controlled manufacturing of nanostructures.

There is no such thing as "a nanotechnology." What we call nanotechnology is not an industry, nor is it a single technology or a single field of research. It consists of sets of enabling technologies applicable to many traditional industries. You often hear nanotechnologies described as a platform technology, meaning technologies so pervasive that they serve as springboards for other technologies and as foundations for many diverse applications.

Computer operating systems are a good example of a platform technology. Rather than having to deal with computer hardware directly, programmers work with an abstraction of the underlying hardware to build diverse applications, from games to control software for nuclear power plants. In a similar fashion, nanotechnologies allow the precise control of individual atoms and molecules, leading to unprecedented ability in many diverse areas to develop new materials, devices, and solutions.

There is no universal nanotechnology definition, and this has created some confusion. The International Organization for Standardization (ISO) defines nanotechnology as the "application of scientific knowledge to manipulate and control matter in the nanoscale to make use of size and structure dependent properties and phenomena distinct from those associated with individual atoms or molecules or with bulk materials."

Early proponents of molecular manufacturing used the term to describe nanoscale machinery such as motors, computers, autonomous robots, and personal nanofactories. Some became frustrated as the term expanded to include anything involving the observation, measurement, or manipulation of matter at the nanoscale.

As a matter of fact, the person credited with coining the term "nanotechnology" in 1974, Norio Taniguchi, didn't use it for sci-fi type machinery but to describe semiconductor processes such as thin film deposition and ion beam milling exhibiting characteristic control on the order of a nanometer.

Today, most definitions revolve around the study and control of phenomena and materials at length scales below 100 nm. Some definitions include a reference to molecular systems and devices, and nanotechnology purists argue that any definition needs to include "functional systems."

Now that we understand what nanotechnology means, the next question is: what's so special about it, and why is it such an important issue now?