Probing Question: What is nanotechnology?

carbon nano tube
Professor Geoffrey Hutchison, University of Pittsburgh

A view down the center of a carbon nanotube

You might not realize it, but there's probably some cutting-edge science in your dresser drawer. If you've ever bought a stain-resistant shirt or wrinkle-proof khakis, then you've experienced products created by one of the hottest arenas in scientific research: nanotechnology.

We've all heard the word, but what does it mean? Says Paul Weiss, professor of Chemistry and Physics at Penn State University Park, nanotechnology generally involves manipulating matter at an incredibly small level—that of the nanometer. (A nanometer is about 100,000 times thinner than a sheet of office paper, and a strand of DNA is about 2 nanometers across.) Those stain-deflecting pants, for example, have a special coating made up of billions of tiny whiskers. The whiskers create a thin cushion of air just above the fabric's surface. You can't see or feel the difference, but spill a cup of coffee and it'll ride that cushion of air right off the fabric. Since the liquid never touches the pants, voila, no stain.

Stain-prevention might seem like a pretty mundane area of scientific study. But Weiss explains the real allure for scientists: in the nano world, the everyday rules of matter become much more flexible. "At these scales a number of interesting properties emerge," he says. "One of the more exciting challenges and opportunities is that much of our intuition fails in that it is generally based on macroscopic measurements." In the nano realm, things can get weird—and very interesting.

Pure carbon, for example, naturally appears in two forms: the diamond in your wedding ring and the graphite in your pencil. However, notes Weiss, when working at the nanometer level, scientists discovered a new, tubular form of carbon. The carbon nanotube has 10 times the strength of steel at only one-quarter of the weight. (Nanotubes have since made for stronger car bumpers and lighter tennis rackets.) When nanoparticles of a substance are mixed with other bulk materials in the production process, new materials are created that are often dramatically lighter, stronger, more stable and functional than the originals.

For scientists, nanotechnology is a doorway into a whole new (infinitesimally small) universe of possibilities. "We are really trying to understand new phenomena and to open up unexplored worlds," says Weiss. "One of the exciting aspects is that nanotechnology has required people from a number of fields to come together—chemistry, physics, biology, materials, electrical engineering, biomedicine, etc.—depending on the particular problems being addressed."

Hybrid fields are emerging at the crossroads of nanotechnology and pharmacology, genetics, aeronautics, and fashion, just to name a few. Researchers are working on a multitude of promising projects, including nano-enabled drug delivery systems that are more targeted and less toxic; super-sensitive nano sensors that help astronomers peer into previously obscured realms of space; and myriad high-tech materials applications, ranging from chip-resistant paint, heat and water resistant windshields, and nano-scale batteries that could someday power our vehicles and computers.

Doing science on the nano-level is exciting, but also presents researchers with plenty of challenges. Simply seeing objects that small was impossible until the 1980s invention of a new branch of microscopy that uses physical probes, instead of lenses, to visualize surfaces at even atomic levels.

But while current nanotechnology has made for better, more effective products—faster computer chips, more effective water-filtration devices, and yes, those stain-free pants—many scientists believe the best is yet to come.

"We imagine wearable computers," Weiss says, "having sensors that tell us when something is amiss, and enhance our ability to perceive the world around us."

In other words, the small world could end up being a very big deal.

Paul Weiss, Ph.D., is a Distinguished Professor of Chemistry and Physics at Penn State University Park. He may be reached at stm@psu.edu.

Last Updated December 08, 2008