Lasers could replace pinpricks for diabetics

To manage their condition, many diabetics rely on home-testing systems to check their blood sugar levels. This involves pricking a finger to draw blood, which can be painful and isn’t ideal if you’re out and about. Now a team from Princeton University Engineering School has developed a new technique that measures blood sugar using lasers – no needles necessary.

In clinical tests, they shot a (harmless) laser at their subjects’ palm, where sugar molecules in the body started to absorb it. This allowed the machine to measure the amount of sugar in the dermal interstitial fluid (a fluid between the layers of skin), which is an accurate gauge of blood sugar.

Medical appliances that make use of lasers usually use the near-infrared frequency, but as it interacts with chemicals in the skin, it wouldn’t be useful in this case. Mid-infrared lasers would be ideal, but are hard to focus. The scientists’ breakthrough came when they used a quantum cascade laser, which, unlike most lasers, can be set to different frequencies. Pointing it to the mid-infrared range meant that they were able to make use of it without it having an effect on the thing they were trying to measure.

So far, it’s slightly less accurate that existing technology but the researchers are working to make it more efficient, and plan to test it on more patients in order to do so. It’s also still too large to be truly portable, but as they continue to refine the design, it should eventually be available for diabetics (and their Star Wars-loving friends) to use at home or out and about.

Image via Princeton University Engineering School.

Diane Shipley