Pain-free glucose test

A SyracuseUniversity chemistry professor has patented a device that aims to make painful fingerstick testing of glucose levels a thing of the past for diabetics.

To address the problems of invasive blood glucose testing, Professor Joseph Chaiken, of the Department of Chemistry in The College of Arts and Sciences, has developed the LighTouch, which accurately monitors glucose levels without a single drop of blood.

The novel procedure uses a laser to measure spectroscopic signals in blood while the blood is still in the capillaries. Abnormal levels of blood components, such as glucose, can be detected without pricking a person’s finger.

The LighTouch uses a method called Raman spectroscopy to focus a laser – which Chaiken refers to as a “CD-player type of laser that has been kicked up a notch to deliver a purer red colour,” – onto the fingertip and analyze the various colours of the light exiting the finger. These colours are indicative of the types and quantities of the different chemicals in the tissue being illuminated by the laser.

By making two such measurements, first with the fingertip under no pressure and the second with slight pressure applied to the flesh, researchers are able to compare the measurements and analyze only those colours that come from the part of the fingertip which moves under slight pressure – the blood. The procedure is completely painless and produces results with accuracy and precision comparable to existing fingerstick devices.

“Just as an electrocardiogram machine (EKG) produces an electrocardiogram, the LighTouch produces a Ramagram,” says Chaiken. Raman spectroscopy is a spectroscopic technique used in condensed matter physics and chemistry to examine vibrational, rotational and other low-frequency modes in a system. It is named for Chandrasekhara Venkata Raman, who won the 1930 Nobel Prize in Physics for discovering “feeble fluorescence,” later known as the Raman effect, in 1928.

Chaiken predicts that the availability of a non-portable glucose machine for the public is still a few years away, depending on FDA approval. The first LighTouch devices will appear in clinics, doctors’ offices and hospitals. The next step would be portable devices that measure glucose, as well as non-portable devices that measure other analytes such as cholesterol, urea and total protein.

Chaiken believes these machines can be developed in the coming years. He holds US and worldwide patents for both the device and measuring process, and has several other patents in process.

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