A carbon nanotube-coated smart yarn that conducts electricity could be woven into soft fabrics that detect blood and monitor health, engineers at the University of Michigan have demonstrated. Currently, smart textiles are made primarily of metallic or optical fibers, which are fragile and uncomfortable; metal fibers also corrode. The new material is more sensitive and selective, as well as more simple and durable than other electronic textiles. Clothing that can detect blood could be useful in high-risk professions.
To make these e-textiles, the researchers dipped 1.5-millimeter thick cotton yarn into a solution of carbon nanotubes in water, and then into a solution of a special sticky polymer in ethanol. After being dipped just a few times into both solutions and dried, the yarn was able to conduct enough power from a battery to illuminate a light-emitting diode device. The yarn turned black, due to the carbon, but it remained pliable and soft. The researchers added the antibody anti-albumin to the carbon nanotube solution since the antibody reacts with albumin, a protein found in blood.