Researchers have developed an implantable sensor that can monitor blood-sugar levels and send the data wirelessly to an external receiver. The team has used the device in pigs for over a year, and is hoping it will work successfully in humans with diabetes.
Diabetics have to routinely measure their blood glucose by pricking their fingers and reading the levels with a small meter, in order to keep the blood sugar in check.
“Four finger sticks per day to measure glucose levels is the current standard of care, but blood glucose can go on significant excursions between sticks,” says David Gough, an author of the study from the University of California in San Diego. “In contrast, the long-term implanted glucose monitor would provide continuous monitoring day and night.” (press release from UC San Diego)
The sensor could aid diabetes patients to adjust the timing and dosage of insulin, as well as minimizing the risk of potentially life-threatening hypoglycaemia—low blood sugar—resulting from too high a dose of insulin or the insulin absorbing too fast. It could also help type-2 diabetes patients to balance their diet and exercise plans.
In the study, published in Science Translational Medicine today (doi:10.1126/scitranslmed.3001148), the team reports inserting the sensors just beneath the skin of two pigs for 222 and 520 days respectively. The device is 1.5 cm thick and has a diameter of 3.4 cm. It works by detecting the amount of oxygen that is consumed in a chemical reaction with glucose, triggered by the enzyme glucose oxidase. The concentration of glucose is proportional to the consumption of oxygen in the reaction.
The authors say that short-term glucose sensors already exist, but they need to be replaced every 3-7 days and haven’t been approved by the Food and Drug Administration as a ”primary standard for glucose measurement”. (Science Translational Medicine, doi:10.1126/scitranslmed.3001148)
The research team has been collaborating with the San-Diego based company GlySens, which Gough started in 1998.
Gough says that he hopes to start the first human trials within a few months.
Image: C. Bickel/Science Translational Medicine © 2010 AAAS