Low-cost sensor detects glucose in sweat

Led by Huanyu “Larry” Cheng, Dorothy Quiggle Career Development Professor in Penn State University's Department of Engineering Science and Mechanics, the researchers have published details of the device in Biosensors and Bioelectronics.

The researchers constructed the device first with laser-induced graphene (LIG), a material consisting of atom-thick carbon layers in various shapes.

Insulin-delivery patch monitors and manages glucose levels

Wearable sensor measures glucose without need for finger-prick blood test

“The challenge here is that LIG is not sensitive to glucose at all,” Cheng said in a statement. “So, we needed to deposit a glucose-sensitive material onto the LIG.”

The team chose nickel because of its robust glucose sensitivity, according to Cheng, and combined it with gold to lower potential risks of an allergic reaction. The researchers hypothesised that the LIG outfitted with the nickel-gold alloy would be able to detect low concentrations of glucose in sweat on the skin’s surface.

According to Cheng, there is a strong correlation between glucose levels in sweat and blood. While the concentration of glucose in sweat is about 100 times less than the concentration in blood, the team’s device is sensitive enough to accurately measure the glucose in sweat and reflect the concentration in blood.