A tattoo that listens to heart and brain

RESEARCHERS IN the US, Singapore and China have developed a flexible monitor that can pick up signals from the body, but rather than being bulky or involving glues or straps, it transfers on to the skin like a temporary tattoo.

How did they do that? Well, they put filamentous, serpentine-shaped electronic circuits and other components, such as sensors and even power sources, on to thin sheets of water-soluble polymer. The PVA polymer acts as a temporary mount for the electronic apparatus and the whole thing is placed on the skin, electronics side down, before the PVA is washed away to leave the electronics in place.

One of the beauties of this approach is that the device, once on the skin, attaches itself through van der Waals forces, so there’s no need for messing around with glue.

Using this “epidermal electronic system”, researchers can measure electrical activity in the heart, brain, and skeletal muscles, as they report in the journal Science. The thin device works even on the throat, where it can pick up muscle activity during speech – the team used it to help control a voice-activated video game.

“Our goal was to develop an electronic technology that could integrate with the skin in a way that is mechanically and physiologically invisible to the user . . . It’s a technology that blurs the distinction between electronics and biology,” writes John Rogers, of the University of Illinois at Urbana-Champaign, in a press release.