New bandage senses temperature, delivers medicine

Engineers have designed a sticking bandage that releases medicine in response to changes in skin temperature.

Designed by Xuanhe Zhao, associate professor at Massachusetts Institute of Technology's department of mechanical engineering, the hydrogel is a rubbery material, mostly composed of water, designed to bond strongly to surfaces such as gold, titanium, aluminum, silicon, glass, and ceramic.

The sticky, stretchy, gel-like band can incorporate temperature sensors, LED lights and other electronics, as well as tiny drug-delivering reservoirs and channels.

"If you want to put electronics in close contact with the human body for applications such as health care monitoring and drug delivery, it is highly desirable to make the electronic devices soft and stretchable to fit the environment of the human body," Zhao said.

The "smart wound dressing" of the device releases medicine in response to changes in skin temperature and can be designed to light up if, say, medicine is running low.

When the dressing is applied to a highly flexible area, such as the elbow or knee, it stretches with the body, keeping the embedded electronics functional and intact.

Zhao said the electronics coated in hydrogel may be used not just on the surface of the skin but also inside the body, for example as implanted, bio-compatible glucose sensors, or even soft, compliant neural probes.

The study was published in the journal Advanced Materials.