The device uses tiny aluminum gallium nitride (AlGaN)/gallium nitride (GaN) high electron mobility transistors to be able to perform detection at the low concentration levels of the breath. In its latest iteration, the sensor was coupled with a wireless system to create a remote monitoring device that, according to the researchers, can do its detecting within five seconds.

[Fan Ren, professor of chemical engineering] said the sensors work by mating different reactive substances with the semiconductor gallium nitride commonly used in amplifiers in cell phones, power grid transmission equipment and other applications.

If targeting cancer, the substance is an antibody that is sensitive to certain proteins identified as indicative of cancer. If the target is glucose, the reactive molecules are composed of zinc oxide nanorods that bind with glucose enzymes.

Once the reaction happens, “the charge on the semiconductor devices changes, and we can detect that change,” Ren said.

While the sensor is not as acutely sensitive as those that rely on nanotechnology, the manufacturing techniques are already widely available, Ren said. The cost is as little as 20 cents per chip, but goes up considerably when combined with applications to transmit the information wirelessly to computers or cell phones. The entire wireless-chip package might cost around $40, he said, although that cost could be cut in half with mass production.