Color-changing tattoo shows blood glucose level

An experimental dermal implant changes color in the presence of high acidity or blood glucose, potentially allowing diabetics and other patients to monitor their wellbeing without taking samples. The implant material can be integrated into tattoo ink formulations, making them as discrete or ostentatious as the wearer wishes.

MedicalXPress:

As detailed in the journal Angewandte Chemie, a colorimetric analytic formulation was injected into the skin instead of tattoo ink. The pigmented skin areas varied their color when blood pH or other health indicators changed. … The authors claim that such sensor tattoos could allow permanent monitoring of patients using a simple, low-cost technique. With the development of suitable colorimetric sensors, the technique could also extend to recording electrolyte and pathogen concentrations or the level of dehydration of a patient. Further studies will explore whether tattoo artwork can be applied in a diagnostic setting.