Temporary tattoos are fun. Or, rather, they used to be fun. A new and far less jolly version have been developed to monitor alcohol levels.
Researchers from the University of California San Diego developed the device for the National Institute of Health’s Wearable Alcohol Biosensor Challenge in 2015. Though this device didn’t win—top honors went to a bracelet similar to a Fitbit—it is continuing to be developed for its inexpensive cost and ease of use.
Patrick Mercier, UCSD electrical and computer engineering professor, told Spectrum that the tattoo uses multiple technologies to make the process less invasive than blood tests and more accurate than breathalyzers.
First, the tattoo, which is screen-printed with silver and silver-chloride electrodes, is placed on the skin. Then, a flexible electronic board attaches to it magnetically. Once attached, the device is activated, generating a small current that triggers a gel strip on the tattoo that then releases a drug into the skin to induce sweat. After reading and processing the alcohol levels, the results are sent to the user’s smartphone via Bluetooth.
Results of the study testing the device were published in ACS Sensors, and Mercier notes that, like all temporary tattoos, the device is disposable and can only be used once. He told Spectrum that they are now working on a version that can continuously track alcohol levels for 24 hours.