Coming Soon to Your Closet: Clever Clothes

Jan. 14, 2008— -- The garments on our backs could do much more than protect us from the cold in the future. They could monitor our health systems, protect us from viruses and possibly even automatically call for help if we are injured.

In the latest round in the quest for clever clothes, researchers at the University of Michigan have developed yarn that looks and acts like regular yarn. But it can detect the presence of blood, making it theoretically possible to make clothes that will alert the command post if a police officer or soldier has been wounded.

The Michigan team has taken the technology beyond the current use of metallic or optic electrical conductors, which tend to be fragile and can rust or corrode.

"We have found a much simpler way, an elegant way, by combining two fibers, one natural and one created by nanotechnology," engineering professor Nicolas Kotov said in announcing the development.

The key to the technology is the use of carbon nanotubes, revolutionary tiny tubes that can be 1/50,000th the thickness of a human hair, but up to 40,000 times as long as they are thick. Nanotubes are extremely strong, and have very useful properties, including the conduction of heat and electricity.

Kotov's team found that if they dipped a piece of cotton yarn into water containing carbon nanotubes, and then into a solution of ethanol with a sticky polymer, the yarn could conduct enough electricity from a battery to illuminate a light-emitting diode.

They then found that if they added an agent to the solution that reacts to albumin, a protein found in blood, the conductivity increased significantly. Kotov suggested that it could be possible to use that change in conductivity to automatically cause a cell phone or other communication device to send a distress signal because of the presence of blood. That could alert authorities even if the person is unconscious.

It's also theoretically possible to use the same technology to monitor various health functions, including blood pressure and pulse.