A team of engineers at UC Berkeley and medical researchers at UCSF have created a “smart bandage” prototype that can detect skin tissue damage in its early stages, allowing medical professionals to discover pressure ulcers and bed sores before they become permanent.

The project is a collaborative effort between electrical engineers at UC Berkeley, who developed the bandage’s software and hardware, and medical researchers at UCSF, who carried out the initial trials on animals. The new technology detects changes in electrical currents to reveal damaged cells in skin tissue, making them detectable by physicians before the wounds become visibly severe.

“Regular tissues will conduct electrical currents in one way, so if you (have) damaged those cells, the electrical currents will change,” said David Young, a UCSF professor of surgery who co-authored the study. “The goal is to eventually have a bandage you can put on patients who are at risk and bedridden to detect pressure ulcers before they actually happen.”

The smart bandage is composed of a thin piece of plastic with gold electrodes printed onto it. These electrodes indicate changes in the tissue through a process called impedance spectroscopy, which detects resistance to the passage of electrical signals by running current through cells.

“(The) idea is like comparing the cells to balloons,” said Yasser Khan, a UC Berkeley doctoral student in electrical engineering and computer science who worked on the electrode sensors. “You can imagine (the skin tissue) as a field of balloons where we can see the healthy cells. What happens is that (when) some of the cells get damaged, like balloons getting popped, and … we can pick up the disturbances in our measurements.”

While the approach is novel, the concept of a smart bandage has been explored by researchers in recent years. In 2014, researchers from the United States, South Korea and Germany developed a membrane-like bandage that indicates oxygen concentrations in skin wounds. The membrane, when treated with chemical dye, displays a green color when the tissue is oxygenated and a red color when the wound requires medical attention.

Conor Evans, an assistant professor at Harvard Medical School who led the research team behind the oxygenation bandage, said the two kinds of smart bandages could be complementary.

“One could combine the type of technology that’s coming out of Berkeley with the (bandage) we’re working on to make something that has extra capabilities, and that can be very powerful for patient health,” Evans said.

While the bandage project led by Evans is expected to be evaluated soon by the Food and Drug Administration and is undergoing human trials, Young said the electrode bandage will take years to be fully developed.