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. When the particles are dissolved in water they look like food coloring, says Clark.
The three parts continuously move around the inside the hydrophobic orb. When they approach the surface, the glucose detecting molecule either grabs a molecule of glucose or the mimicking molecule.
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.
Wow. I remember the experience of trying to figure out an easy way for an elderly gentleman to figure out how to manage his own insulin at home. A shoebox with holes cut into it with the sliding-scale written underneath the holes was a pretty good idea supplied to me by a more experienced nurse, but this sounds like it could be lots of fun.
When I read this article, I initially imagined a tattoo in the shape of a thermometer, with color-changing segments indicating one of the usual six cases of sliding scale insulin coverage (take 3u, 6u, 9u, 12u, eat a muffin, call a doctor). Think of the customization options!