Scientists have created an inexpensive ‘smart’ bandage-like plaster that collects sweat by replacing blood sampling from the skin, as it doesn’t incorporate any electronic components and get rid of having blood sample.
When the biosensor is applied to a patient’s skin like a bandage, their perspiration gets channeled into those microwells, where it collects. Dyes applied to the bottom of each well subsequently change color according to the sweat’s pH level, and its concentrations of chloride, glucose and calcium.
A smartphone camera and app are then used to assess the color of the wells, providing users with a readout of the four parameters although the data is obtained from sweat, it corresponds to levels within the patient’s body.
When tested on a volunteer who was perspiring as they exercised, the device/app determined that their sweat had a pH level of 6.5 to 7.0, a chloride concentration of about 100 mM (nanomolars), and trace amounts of calcium and glucose.
The scientists from the University of Science and Technology Beijing, the Chinese Academy of Sciences, the California Institute of Technology, and the University of California-Davis are now working on improving the device’s sensitivity.