Tattoo Could Measure Blood Glucose in Diabetes
Among the most common wish of people with diabetes is a way to measure blood glucose without needles. A group of nanoengineers has developed a temporary tattoo that could grant that wish, but it’s still in the testing stages.
Needle-less measurement of blood glucose levels has been a goal of numerous researchers for many years, and the quest has resulted in some innovative approaches, which are explained later. Among the latest is a temporary tattoo, which is the brainchild of a team at the University of California, San Diego, headed by graduate student Amay Bandodkar.
The team conducted a proof-of-concept study, which involved, among other tests, applying the tattoo to the skin of seven men and women who were free of diabetes. Glucose measurements were taken after all the volunteers consumed a meal rich in carbohydrates.
The researchers noted that the tattoo detected the rise in sugar levels after the meal just as well as did use of a traditional finger-stick glucose device. None of the participants said the test was uncomfortable, although a few did report some mild tingling within the first 10 seconds of starting the test.
The tattoo (classified as an iontophoretic biosensing system or electrochemical biosensor) is applied to the skin for 10 minutes. A constant, low level electrical current is used, which causes sodium ions present in the fluid between skin cells to move toward the electrodes on the tattoo.
Glucose (sugar) molecules piggyback on these ions, and a sensor in the tattoo measures the strength of the electrical charge produced by the sugar, which in turn reveals the individual’s glucose levels. A previous device (GlucoWatch; Cygnus Inc.) that was tested more than a decade ago caused skin irritation, but the new tattoo utilizes a lower electrical current that has not caused this side effect.
The tattoo is not yet ready for prime time, as more tests are needed. In addition, the tattoo currently does not provide a numeric readout for patients, but other researchers are currently developing this complementary instrument.
Other needle-less glucose testing
Experts have been working on a number of other needle-less methods of testing glucose. Among them are the following:
- A team at Purdue developed a nanostructured biosensor capable of detecting glucose in tears, saliva, blood and urine.
- A study at Western New England University has been exploring the use of breath to detect glucose levels
- At the University of Michigan, experts are looking at how to use tears to detect sugar levels
- Google is not just a search engine; the company has also been working on a contact lens designed to measure glucose
For now, people with diabetes must deal with needle sticks to test their blood glucose levels. Given all the innovative options that are under investigation, hopefully at least one will soon be ready for the market. As for the new tattoo glucose device, the authors believe it “hold considerable promise for efficient diabetes management” and could be used as well to monitor other substances found in the fluid between cells.
Bandodkar AJ et al. Tattoo-based noninvasive glucose monitoring: a proof-of-concept study. Analytical Chemistry 2015; 87(1): 394-98