Soon, laser device to measure blood sugar levels

Diabetics may soon monitor their blood glucose levels without pricking themselves to draw blood as researchers have developed a way to use a laser to measure people's blood sugar.

"With this work we hope to improve the lives of many diabetes sufferers who depend on frequent blood glucose monitoring," said Claire Gmachl, a professor at Princeton University in the US.

The researchers measured blood sugar by directing their specialised laser at a person's palm. 

The laser passes through the skin cells, without causing damage, and is partially absorbed by the sugar molecules in the patient's body. 

The researchers used the amount of absorption to measure the level of blood sugar.The breakthrough came from the use of a new type of device that is particularly adept at producing mid-infrared frequencies - a quantum cascade laser.

For the study, the researchers used the laser to measure the blood sugar of three healthy people before and after they each ate 20 jellybeans, which raise blood sugar levels. 

The researchers also checked the measurements with a finger-prick test. They conducted the measurements repeatedly over several weeks.

Their results indicated that the laser measurements readings produced average errors somewhat larger than the standard blood sugar monitors, but remained within the clinical requirement for accuracy.

"Because the quantum cascade laser can be designed to emit light across a very wide wavelength range, its usability is not just for glucose detection, but could conceivably be used for other medical sensing and monitoring applications," Gmachl said. The study appeared in the journal Biomedical Optics Express.