Researchers from the University of California, San Diego have developed a rub-on tattoo that can monitor blood glucose levels in people with diabetes.

The research team, led by Amay Bandodkar has published a proof-of-concept study showing that the temporary tattoo based glucose sensor they have developed works on humans.

The technology behind the tattoo-based sensor builds upon previous devices such as the GlucoWatch Biographer, a glucose sensor which was worn on the wrist as a watch is. The technology involves applying a small current to the skin which allows the glucose level of cells just under the skin to be measured.

The GlucoWatch Biographer was approved by the FDA and had initial success but ultimately failed to catch on, partly because of its expense but also because users experienced skin irritation which could, at times, be painful.

Improving on the previous technology

The tattoo-based glucose sensor improves upon the GlucoWatch in a number of ways, being smaller, much less expensive to produce and allows a gel to be used under the rub on surface that improves skin contact which improves reliability of the results and reduces skin irritation.

The tattoo was tested on 7 participants without diabetes and was shown to be able to detect changes in blood glucose levels in the presence of natural interfering chemicals. Participants reported only a mild tingling of the skin under the electrodes of the tattoo.

The next steps for the researchers will be to develop their concept further to power the sensor over a longer period of time and to incorporate wireless communication with a handset to view the readings on.