UC Berkeley sensor can measure sweat in real-time

Scientists from UC Berkeley have created a wearable sensor that can measure sweat in real-time. The sensor is thought to one day allow the monitoring of vital health statistics without having to prick the skin and draw blood. The hope is that the wearable sensor might be able to monitor sweat in real-time and provide information on issues like dehydration and fatigue.The sensors can be made rapidly by using a roll-to-roll manufacturing process that prints the sensors onto a sheet of plastic similarly to how newspapers are printed. The goal of the sensors is to decode sweat composition and to do so the scientists say that we need sensors that are reliable, reproducible, and can be fabricated to scale so the sensors can be placed on different parts of the body.

The sensors contain a spiraling microscopic tube or microfluidic that can wick sweat from the skin. The sensor tracks how fast the sweat moves through the microfluidic to see how much the person is sweating. The microfluidic also has chemical sensors that can detect concentrations of electrolytes like potassium and sodium along with metabolics like glucose.

In experiments with humans wearing the sensor while exercising, the team found that sensors located on different parts of the body, like the forehead, forearm, underarm, and upper back, were able to measure the seat rate, sodium, and potassium levels while they exercised. Local sweat rate could indicate the body's overall liquid loss during exercise and could be a way for athletes to get a heads up when they are pushing themselves too hard. The team did find that a single sweat glucose measurement can't necessarily indicate a person's blood glucose level.