Researchers have developed a biosensor capable of monitoring blood glucose levels through the wearer's sweat and tears, according to a study published in ACS Nano.

The continual monitoring of blood glucose for diabetic patients could be improved with wearable sensors, but current biosensors are unable to detect low level of glucose in sweat and tears. In this study, researchers outline the development of a thin and flexible sensor that could be utilized in contact lenses or watches for real-time glucose tracking.

The biosensor was made using nanoribbons of indium oxide, a chitosan film and single-walled carbon nanotubes. When glucose is present, an interaction occurs with the enzyme and creates a chain of reactions that produce an electrical signal.

In testing the sensor, researchers found it was sensitive enough to detect glucose from concentrations of 10 nanomolar to one millimolar. Additionally, the film within the sensor was bent 100 times and did not alter its performance.