A tattoo that monitors blood sugar levels for diabetics is especially interesting to me. I suffer from type II diabetes and should regularly monitor my blood sugar levels. I don’t. I usually monitor only after an unusual eating experience to see how I’m doing. I alter meals as needed If blood sugar goes above a certain level. One reason I don’t monitor sugar levels all the time is the inconvenience of dragging out the monitor and pricking my finger several times a day. A continuous indicator that changes color with sugar levels would make this task much easier. Since I paddle in long distance training sessions, marathon races and exploration trips a sugar level indicator that is constantly visible while performing vigorous activities would be a great help. Persons with type I diabetes could benefit even more from an easily visible continuous monitoring system.
Most continuous blood sugar monitoring is done with an implantable device that is analyzed after a short time to indicate sugar levels during that time. Not very convenient if you need to know sugar levels instantly. Another method uses an enzyme that breaks down glucose. An electrode placed near the skin calculates sugar levels based on this reaction. This method is not approved for use longer than seven days. I found two other methods that don’t have such short working lives. These methods are similar, or even the same, utilizing “inks” that are injected below the skin–much like a tattoo.
Heather Clark with Draper Laboratories, reported in early 2009, started using a sodium sensitive ink originally designed to monitor heart health and electrolyte levels in the body. Heather modified the solution to react with blood sugar. The nano-ink consists of tiny spheres containing a glucose detection molecule, a false glucose molecule, and a color changing solution. The detection molecule interacts with glucose, when present, or the doppelganger molecule when injected under skin. The interaction of the constituents and corresponding color change from a healthy orange to an unhealthy purple indicates the level of glucose. One problem is that skin sugar level detection may be 20 minutes behind blood sugar levels.
Paul Barone and Michael Strano at MIT are working with polymer bound carbon nanotubes in a saline solution injected under the skin. This technology was reported in a 2009 issue of ACSNano The solution fluoresces, revealed by near-infrared light, when it encounters glucose. The “tattoo” is refreshed after a period of months.
An easily visible tattoo that indicates blood sugar levels would be a boon for athletes with diabetes. During periods of hard work, exercise, or competition anyone can know sugar levels at a glance. Since I am a marathon paddler I could know almost instantly whether to take in more “fuel.” I’m not enthused with tattoos but I think I’ll give this one a try.