This type of tattoo won’t disappoint your mom. A health-monitoring sensor can be attached to your arm with a temporary tattoo. The blue smiley-face “tattoo” hides medical sensors that monitor your skin’s pH levels. The sensors can detect and relay information about metabolic stress from exertion to your doctor.
The temporary tattoos are made just like the ones little kids get in grocery store vending machines, except these contain ion-selective electrodes (ISE). The eyes of the smiley face are working electrodes, while the ears are where doctor’s measurement devices can be attached to extract the data.
Researchers at University of Toronto Scarborough invented the sensor tattoo, which has a number of suggested uses. The University of Toronto writes that the tattoo sensors can “give clues to underlying metabolic diseases such as Addison’s disease, or simply signal whether an athlete is tired or dehydrated during training.”