The development of a "nano-tattoo" by Heather Clark, an associate professor of pharmaceutical sciences in Northeastern University's Bouvé College of Health Sciences in Boston, US, could eradicate the need for diabetics to check their blood sugar levels by pricking into their fingers.
With this outwardly invisible tattoo, a special nanoparticle solution is used instead of conventional tattoo colour pigments. The solution is composed of 120 nanometre-sized particles. These particles contain sensor molecules which react with sodium or glucose, creating "biomarkers". When exposed to an ultraviolet light, these biomarkers start to shine. The higher the concentration of the biomarkers the stronger the reaction.
The ultraviolet light, which is required to make the tattoo visible, could be provided by a converted iPhone. The problem is that the device is currently not able to evaluate how strong the light is. At present this task is performed by an extern computer. Clark and her team are already working on programming a corresponding app that will do this evaluation.
Apart from measuring blood-sugar levels, there are also several other possible applications, for instance: measuring the sodium level of long-distance runners to let them know when they should drink; or the monitoring of renal function during operations.