Carbon-Nanotube Thread

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The work "will open an avenue to a new generation of wearable materials," predicts Hinestrosa. He says that Kotov's nanotube-coated cotton "keeps the properties of the textile and adds new functions." Albumin-sensing clothing for soldiers could alert remote medical teams to the fact that a soldier is bleeding, says Kotov. The change in current indicating the presence of a wound could be picked up by a wearable computer that would then send out a message. Textiles incorporating antibody-treated nanotubes could also alert the wearer to allergens by illuminating LEDs or sending a message to a cell phone. Clothing incorporating multiple strips of sensing fabric, each targeted to a different biomarker or to parameters like temperature, would be capable of more-sophisticated monitoring of vital signs.

"We're getting closer to the goal of intelligent textiles," says Pulickel Ajayan, a professor of mechanical engineering and materials science at Rice University. Kotov's work, he says, is a good demonstration that textiles incorporating nanomaterials can do more than just conduct electricity.

The advantage of incorporating carbon nanotubes into textiles, says Hinestrosa, is that they can perform many different functions, making it unnecessary to add on extra, bulky components. "You can use the same threads as conductors, sensors, and as transducers of the signal," he says. For example, in clothes that adjust to the weather, carbon nanotubes could sense the temperature, carry the reading to a wearable computer, then carry a signal from the computer that directs the fibers to conform to a more open weave if it's hot out.

Kotov notes that his textiles' biosensing mechanism, which relies on changes in current, is uncomplicated. In the simplest possible scenario, the change in current indicating the presence of a protein of interest can be read using nothing more than a battery and a lightbulb. "Despite the simplicity of the concept, the sensitivity is amazing," Kotov says. By contrast, conventional methods for identifying proteins require multiple preparation steps in a wet lab and fluorescence imaging equipment.