Wearable Tattoo Detects Alcohol Levels in Human Sweat

National Institute of Biomedical Imaging and Bioengineering (NIBIB; Bethesda, MD, USA) developed the prototype noninvasive alcohol-monitoring platform, which integrates an iontophoretic-biosensing temporary tattoo with flexible wireless electronics. The device is based on the transdermal delivery of pilocarpine, a drug that induces sweat via iontophoresis. Ethanol can then be detected using an alcohol-oxidase enzyme and a Prussian Blue electrode transducer.

The new skin-compliant biosensor displays a highly selective and sensitive amperometric response to ethanol. On-body results with human subjects show distinct differences in current response before and after alcohol consumption, reflecting the increase of ethanol levels. The skin-worn sensor is coupled with a flexible electronics board that controls the iontophoresis an amperometry operation and data transmission in real time via Bluetooth communication to a smartphone app. The study was published in the July 2016 issue of the ACS Sensors.

“Measuring alcohol in sweat has been attempted before, but those technologies took 2-3 hours to measure alcohol levels,” said senior author Patrick Mercier, PhD, of the UCSD Jacobs School of Engineering. “Our patch sends alcohol levels to your smartphone in just eight minutes, making real-time alcohol monitoring possible, practical, and personal.”

“It resembles a temporary tattoo, but is actually a biosensor patch that is embedded with several flexible wireless components,” commented Seila Selimovic, PhD, director of the NIBIB Program in Tissue Chips. “One component releases a chemical that stimulates perspiration on the skin below the patch. Another component senses changes in the electrical current flowing through the generated sweat, which measures alcohol levels and sends them to the user's cell phone.”

According to the researchers, the new wearable monitor has the advantage of being non-invasive and unobtrusive, which makes it ideal, for example, in a bar, where it could potentially aid people to self-monitor their alcohol intake and avoid driving if they have had too much to drink.

Related Links:
University of California, San Diego
U.S. National Institute of Biomedical Imaging and Bioengineering