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With all the fancy developments in modern medicine, why can’t physicians just take a look at people and diagnose the problem? Recent developments suggest a speedier approach to medical diagnostics may be not too far in the future. At the University of Toronto, researchers have invented a smiley face temporary tattoo that works as a medical sensor, giving doctors detailed feedback on patients’ metabolic stress at a glance. The tattoo’s eyes are actually electrodes, and the ears are points where a measurement device can be clipped in. The devices pick up changes in the skin’s pH levels that indicate when the body is under stress. The stick-on tats can shed light on whether the wearer is dehydrated, fatigued, or if there’s a deeper disorder causing metabolic mischief.

What’s the Deal

Wireless tracking devices are old news in the medical technology world. Since 2011, doctors have used mobile monitors to keep tabs on patients at risk for heart attack, pulmonary disease, and other conditions. Researchers and sports trainers use ion-selective electrode (ISE) devices to study all kinds of pathways and processes that happen under the skin. Preventative technological gadgets like ISEs (as well as more everyday stuff like health-related smartphone apps) fall under the geeky umbrella of mobile health, or mHealth. “mHealth,” a term coined in 2010, is a new branch of medicine that uses mobile technology to keep tabs on everyday activities in order to improve healthcare and preventative treatmentsThe promise of mHealth: daily activity monitoring and outcome assessments by wearable sensors. Dobkin BH, Dorsch A. Department of Neurology, Geffen UCLA School of Medicine, Los Angeles, CA, USA. Neurorehabil Neural Repair. 2011 Nov-Dec;25(9):788-98..

Why It Matters

The new ISE tattoos put older, bulkier external devices to shame. The geek-chic monitors can be attached to any commercially available temporary tattoo — Disney or X-Men fans, rejoice! In addition to looking neat-o, they’re sweat-proof, durable, and can be attached to any exposed skin surfaceTattoo-based potentiometric ion-selective sensors for epidermal pH monitoring. Bandodkar AJ, Hung VW, Jia W, Valdés-Ramírez G, Windmiller JR, Martinez AG, Ramírez J, Chan G, Kerman K, Wang J. Department of Nanoengineering, University of California San Diego, La Jolla, CA, USA. Analyst. 2013 Jan 7;138(1):123-8..The researchers created the tattoos with a run-of-the-mill screen printer and adhered them to the test subject’s bodies with, obviously, a damp paper towel. The stretchy and sticky nature of the tats means that they can hold on through all kinds of physical activities, providing scientists and doctors with real-time pH readings of human perspiration. The sensors can be modified to pick up different readings, like sodium and potassium levels in perspiration. This is the first fully body-integrated tech device, and the possibilities for tweaking the sensors to recognize other conditions are nearly limitless.

Right now, the University of Toronto team hasn’t released any plans to expand their technology for commercial use. Researchers from the University of Illinois Urbana Champaign, who have developed a similar product, originally hoped the tiny sensors would be useful in monitoring vital stats for premature babies.

What medical procedure would you like to see in tattoo form? Tell us in the comments below or tweet the author at @SophBreene.

Photo by Ken Jones