Lasers could provide non-invasive method for glucose measurement

Researchers at Princeton University have devised a new method to measure glucose levels that requires only a beam of light and the palm of a hand, according to research published in Biomedical Optics Express.

Now working to shrink the laser system to a portable size, Sabbir Liakat, a graduate student in electrical engineering, and colleagues are hopeful the technique could provide a new non-invasive testing path for patients.

“This summer, we are working to get the system on a mobile platform to take it places such as clinics to get more measurements,” Liakat said in a press release. “We are looking for a larger dataset of measurements to work with.”

Using mid-infrared quantum cascade laser spectroscopy, the team of researchers was able to non-invasively predict blood glucose concentrations of three healthy people.

The system delivers and collects light through a hollow-core fiber-based optical setup, then uses the broadly tunable laser to obtain spectra and standard chemo-metric techniques (partial least squares regression) for prediction.

The laser causes no damage when passing through the skin cells, and gets partially absorbed by the sugar molecules in the body, according to the release. The amount of absorption is used to measure blood glucose level.

The researchers reported clinically accurate predictions 84% of the time, on average, throughout a glucose concentration range of 80 to 160 mg/dL. Glucose monitors are currently required to produce readings within 20% of actual levels, according to the release.

“We are working hard to turn engineering solutions into useful tools for people to use in their daily lives,” Claire F. Gmachl, Eugene Higgins Professor of Electrical Engineering and researcher on the project, said in the release. “With this work we hope to improve the lives of many diabetes sufferers who depend on frequent blood glucose monitoring.”

Disclosure: See the full study for a complete list of the researchers’ financial disclosures.