Diabetes: a temporary tattoo to measure glycaemia

Epidermal tattoo for diabetes diagnostics
Epidermal tattoo for diabetes diagnostics

Nowadays, nearly 350 million people have diabetes around the world. This disease, characterized by a high blood glucose level, is one of the leading causes of death and of serious cardiovascular and renal complications.

 

In order to control their glycaemia, a number of insulin-dependent diabetics need to test their blood glucose level several times a day by pricking their finger to collect a blood sample. This painful and difficult to perform experience will soon tend to disappear thanks to a new device measuring blood sugar, developed by nanoingineers, Amay Bandodkar and colleagues, in University of California.

 

How many diabetics have always dreamed of suppressing the burden of pricking their finger several times a day to check their blood glucose level? Some researchers at the NanoEngineering Department of UC San Diego may have found the solution to their problem. Indeed, they have been developing a temporary tattoo to measure patients’ glycaemia in the fluid between skin cells and extract information. This innovative device is noninvasive, painless and easy to wear. The new glycemic monitoring device is also very cheap (only a few cents/tattoo) and simple to produce. Electrodes are printed on a temporary tattoo paper. When this tattoo is positioned on the patient’s skin each day, a mild electrical current is applied for 10 minutes on the skin to make the sodium ions in the fluid between skin cells migrate towards the electrodes. These sodium ions carry glucose molecules; therefore the strength of the electrical charge measured by the sensor is correlated to the glucose level. However it is important to note that in this fluid, concentration of glucose is 100 times lower than blood; the sensor in the tattoo is highly sensitive.

 

Epidermal diagnostic device combining reverse iontophoretic extraction of interstitial glucose and an enzyme-based amperometric biosensor

Epidermal diagnostic device combining reverse iontophoretic extraction of interstitial glucose and an enzyme-based amperometric biosensor

 

A similar patch, GlucoWatch, had been developed in 2002 by the company Cygnus but was never widely used because of the skin irritation it caused. The new tattoo has been tested on 7 men and women from 20 to 40 years old without any diabetes history. After having a rich sugar meal, they used applied the tattoo to measure their glycaemia and no incomfort nor pain was felt except for a slight tingling when the tattoo sensor was taking measurements.  The tattoo’s measurements were completely consistent with a traditional blood glucose finger-prick testing. Nowadays, researchers in Massachusetts Institute of Technology Department of Chemical Engineering are working to develop a nanoparticle ink tattoo that, after being injected under the skin with a sensor, could monitor glycaemia for up to 6 months before needing to be refreshed. It has however never been tested on humans.

 

A study published by the New England Journal of Medicine in 2008, has shown that continuous glycaemia monitoring helps diabetic patients to better control their blood glucose level. Diabetes major complications result from short excursions of a patient’s post prandial blood glucose level outside of the physiological normal range. The prevention of these excursions thanks to the tattoo glycaemia monitoring would help reducing patients’ complications, and as a consequence, diabetes morbidity.

 

Researchers are currently working to provide a numerical reading that patients will need to monitor their condition. They hope the tattoo will be approved for use without any finger prick test backup monitoring required. In the future, this tattoo device could explore many other body metabolites like lactate to monitor athletes’ condition, or to detect alcohol and drugs.  It could eventually be used to test a new drug’s efficacy during clinical studies or perhaps be a noninvasive alternative way to deliver drugs.

 

To conclude, this tattoo measuring glycaemia is a very promising device in monitoring diabetes which will certainly improve diabetics’ quality of life. Coupled to Bluetooth, it would eventually be able to send patients’ information to their doctor and generate real time data.

 

 

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