(HealthDay News) — An experimental device uses a patch to monitor blood glucose levels via sweat, and delivers metformin through the skin with microneedles, according to findings published in Nature Nanotechnology.

Dae-Hyeong Kim, PhD, from the Seoul National University in South Korea, and colleagues used graphene to develop a thin, flexible patch that contains a variety of sensors that detect humidity, sweat glucose levels, pH, and temperature that can be used for diabetes monitoring. In addition, the patch contains heat-sensitive microneedles.

The researchers tested the glucose-sensing ability of the patch in 2 humans and found the device was able to accurately measure blood glucose levels. The team used microneedles to deliver metformin to mice. Over 6 hours, the drug — delivered through the skin — was able to lower glucose levels from 400 mg/dL to 120 mg/dL.

The researchers said their next step is to improve the long-term stability and accuracy of the blood glucose sensor.


  1. Lee H, Choi TK, Lee YB, et al. A graphene-based electrochemical device with thermoresponsive microneedles for diabetes monitoring and therapy. Nat Nanotechnol. 2016. doi:10.1038/nnano.2016.38.