People get tattoos for a variety of reasons, such a s remembering a person or event, or just for aesthetic reasons. And thanks to researchers of MIT and Harvard, another reason can be added to that list: checking your health. Aiming to go beyond wearables with a project that combines art and medicine, the researchers developed smart tattoo ink that changes colour when your blood sugar drops or you are dehydrated!

The drawback of current wearable monitoring devices is that they don’t seamlessly integrate with the body. In addition, short battery life or the need for conductivity also poses a problem with current technology.

The newly developed tattoo inks change colour according to the chemistry of the body’s interstitial fluid, which can be used as a surrogate for constituents of the blood, eliminating the need to draw blood. One ink changes from green to brown as glucose concentration increases.

The team has also developed green ink, viewable under blue light, that grows more intense as sodium concentration rises, an indication of dehydration. Researchers tattooed the inks onto segments of pigskin and noted how they changed colour or intensity in response to different biomarkers.

The project, called Dermal Abyss, was conducted as a proof-of-concept. The team needs to work out some kinks, such as stabilizing ink so designs don’t fade or diffuse into surrounding tissue. Once that is done, the ink could be incorporated into long-lasting tattoos for chronic conditions or into temporary designs for shorter-duration monitoring. Another possibility is invisible ink that reacts to a particular kind of light.

Photos: Harvard / MIT