Look at a single fiber in your tee-shirt. Or a hanky. Now, imagine that fiber 1,000 times smaller.

It will take a stretch of the imagination, because that would make the fiber roughly the size of an air molecule — and to see that, you’d need a high-powered electron microscope.

But, scientists are working with fibers that small, nanofibers, and the things they’re accomplishing may well revolutionize the world of textiles, including uses of cotton.

While you’re in the imagining mode, consider these science fiction-like projects using nanofibers:

• Polymers tailored to absorb pesticides, herbicides, fertilizers, etc. Margaret Frey, in Cornell University’s Department of Textiles and Apparel, says the fibers could be saturated with timed-release pesticides or other crop chemicals/nutrients and incorporated into the soil at planting.

She and her colleagues, entomologist Mike Hoffman and horticultural scientist Alan Taylor, say the goal is to develop a textile that would “not only biodegrade by the end of the growing season, but would replenish the soil with nutrients as it degrades.”

The materials would “go exactly where farmers want them to go,” resulting in reduced use and the pesticide or nutrient “doing its job and nothing else.”

• A shirt, blouse, or other garment made of cotton threads coated with a thin layer of semiconductor polymers and nanoparticles that conduct electric and can power your cell phone or iPod or monitor your heartbeat, brainwaves, and other functions.

“The fabric will bend the same, drape the same, feel the same,” says Juan Hinestroza, also in the Cornell textiles/apparel department. The wearer “will never notice” any difference between the conductive material and regular cotton fabric.

• Textiles that can act as sensors that could be used to detect the presence of hazardous bacteria, such as E. coli or anthrax. The material, perhaps in the form of a sponge, Frey says, would be “something that people without a high level of training could use fairly quickly” to provide an instantaneous alert of a contaminant.

• Protective clothing that selectively blocks hazardous gases and minuscule contaminants, but allows air and moisture to flow through so the wearer can sweat and feel comfortable. These garments would be particularly useful for firefighters, emergency responders, or military personnel on duty in tropical climes.

• “Smart” clothes made of fibers that can change colors — one appropriate for daytime business environment, a different one for nighttime socializing.

• Fabrics that could provide timed-release of medicines. “You could have your arthritis medicine while wearing your gloves,” Hinestroza says.

• Magnetic nanoparticles embedded into fabric or paper to provide a unique but invisible signature to prevent counterfeiting of documents, passports, or designer clothing.

While it may all have a science fiction tinge, Hinestroza and Frey say nanotechnology will change many of the products we use and have a market impact in the hundreds of billions of dollars — with textiles representing an important share of that market.

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