Diabetics monitoring their glucose levels may soon put the days of painful finger-sticks behind them. Instead, they can go through the one-time ordeal of getting inked with a nanoparticle tattoo. Heather Clark, a scientist at Draper Laboratories, has developed a nano ink particle that constantly samples glucose levels in the skin. Injected subcutaneously, the ink changes color in response to glucose content.
The nano ink particles are tiny, squishy spheres about 120 nanometers across. Inside the sphere are three parts: the glucose detecting molecule, a color-changing dye, and another molecule that mimics glucose.
If the molecules mostly latch onto glucose, the ink appears yellow. If glucose levels are low, the molecule latches onto the glucose mimic, turning the ink purple. A healthy level of glucose has a “funny orangey,” color, according to Clark. The sampling process repeats itself every few milliseconds.