New light sensor makes painful pinpricks history for diabetics

Say goodbye to good old needles, as scientists have found on new method to measure blood sugar with help of light sensor, which doesn't involve taking the blood.

The scientists have developed the sensor "Glucolight", which gages the blood sugar level through the skin. Although skin sensors already exist, they have to be calibrated before use, which means that the skin's permeability value needs to be known. In order to establish this, the blood sugar value has to be determined via a blood sample and the glucose concentration on the skin measured. Based on these readings, the permeability can then be calculated and the sensor calibrated.

Glucolight enables the blood sugar level to be monitored permanently thanks to the sensor's novel measuring technology, which comprises several parts: A microdialysis measuring head, with a "smart" membrane; light sources; a pump; and a microfluidics chip with a fluorometer.

The measurement involves sticking the measuring head, which is around three centimeters in size, to the skin and irradiating it with visible light; some glucose molecules diffuse through the membrane from the skin. On the other side of the membrane, the glucose is mixed with a fluid and pumped through the microfluidics chip, while enzymes are added to trigger a reaction. During the reaction, a fluorescence appears, which the fluorometer measures, and the computer uses the reading to calculate the glucose concentration. The process is then repeated with UV light. The computer then uses these two different readings to calculate the blood sugar level.

The researchers filed a patent application for Glucolight in mid-2014 and the first clinical studies are scheduled at the University Hospital Zurich for 2015. However, it could be years before the use of Glucolight becomes standard.