Tiny, multipurpose sensors, based on flash memory, could detect everything from blood pressure to toxic compounds. The sensors, invented by Edwin Kan, professor of electrical and computer engineering at Cornell University, are now being developed for commercial use by Transonic Systems in Ithaca, NY. The first such application, which could be available in five years, will probably be for studying and monitoring blood flow, pressure, and temperature in the small blood vessels of lab animals, an important part of drug trials, says Transonic project engineer Bruce McKee. In such an application, the sensors would be implanted in the bloodstream of animals.
The sensors are so small and consume so little power, McKee says it's possible they could be permanently implanted in the human body, along with a radio for communications and a power source. Such an implant could continuously monitor the health of organs or levels of certain compounds. Or an implanted pressure sensor, he says, might be useful for monitoring the pressure inside the eyes of those with glaucoma, a leading cause of blindness that's associated with increased eye pressure.
Kan has built prototype sensors measuring 100 micrometers on a side, but says they could be made much smaller. Right now, the sensors communicate their information and receive power via wires. Adding a radio and power for a permanently implantable wireless device will increase the overall size to a couple of square millimeters, Kan says.