istock_99xsmallTattoos as markers have been around forever but there is a new group on the horizon. A group of people so far no-one would have thought of as likely candidates for a tattoo. In fact, they are often advised against having a tattoo due to their compromised skin healing ability. This group is diabetics. Now, why would a diabetic be so foolhardy as to consider having a tattoo, much less a doctor actually prescribe one?
What is one of the banes of a diabetic’s life? Ask one and chances are the answer will be the daily pinpricks to measure blood glucose level among others. Imagine if that one part of the trials of diabetes could be eliminated and a diabetic never had to draw blood to check for glucose again? Well, the day is nigh. It appears that one small tattoo could replace the often painful finger-pricks that diabetics endure up to twelve times a day to monitor their blood glucose levels.

Scientists at the Cambridge-based Draper laboratories are further developing nanoparticle tattoo ink that changes color to indicate glucose levels in the skin. The ink is composed of a glucose-detecting molecule, a color changing dye, and a molecule that mimics glucose, all of which float in spherical polymer bead.

When a glucose-detecting molecule approaches the edge of the bead, it should latch onto either a glucose molecule or the glucose-like molecule. If glucose levels are high, the detecting molecule should attach to glucose in the bead, making the ink appear yellow. If glucose levels are low, the molecule should latch onto the glucose mimic, causing the ink to turn purple. A healthy level of glucose would be represented by a color somewhere in between.

The team’s original goal was not to produce a glucose-measuring ink. They were trying to find one to measure sodium levels in the skin. When that project showed promising results in mouse trials, the director of the bioengineering department at the time challenged the researchers to apply a similar approach to glucose.

One concern about the technology is whether glucose measurements taken from the skin are as accurate as those taken from the blood. Others are whether this technology—which is still years away from being tested in humans—would work equally well through different skin pigments. We won’t know for years yet, but the prognosis seems good.