This week research from a group of UCSD scientists has been getting a lot of attention. They have designed a clear patch that can monitor glucose levels.
This is important, and could be very lucrative, because the number of people with Type II Diabetes mellitus is steadily rising thanks to our sedentary over-fed lifestyles. Currently, most people with Diabetes have to monitor their blood glucose levels by pricking a finger with a needle and squeezing a drop of blood into a glucometer. Some patients, usually with Type I, or insulin dependent Diabetes, can continuously monitor their glucose levels via a microneedle inserted into their skin. Glucose levels in blood and skin are not the same but do correlate, so either can be used to monitor diabetic control. Both of these options are invasive, uncomfortable and can cause infections.
So, finding a non invasive way to monitor glucose is a hot field of research right now.
The glucose-monitoring patch, which the scientists say is like a ‘typical rub-on temporary tattoo’, contains two electrodes that are used to run a mild electric current across the skin surface. The current causes sodium ions, which are positive, to migrate through the skin tissue towards the electrode on the skin surface. The sodium ions ‘pull’ glucose with them. The patch also contains an enzyme that reacts with glucose and can give a read out of skin glucose levels.
This is the same technology that the company Cygnus Inc used to make their now defunct GlucoWatch. The watch was discontinued because it caused skin irritation. The patch gets around this problem by using lower current than the GlucoWatch and having a cool layer of hydrogel on the skin side of the patch. The people who the patch was tested on said they only felt mild tingling for ten seconds while their skin glucose was being measured.
The scientists successfully used the patch to monitor blood glucose levels in people before and after a meal. They did concurrent blood glucose testing using a traditional glucometer and found that the results from the patch correlated well with those from the glucometer.
This is an encouraging result. However, this was a small proof of concept study. The scientists only tested seven people – all of whom were healthy and not diabetic. They also only tested these people before and after eating. Eating causes a big difference in glucose levels. The patch needs to be investigated on more people and over a longer period of time, and under different fasting and dietary conditions.
Also the patch technology can’t do continuous monitoring yet, but the scientists are working to adapt it so it can. They are also working to hook the patch (hopefully wirelessly) to a device to collect and store the information on glucose levels.
The Scientific Paper: