A new, first-of-its-kind device has been developed by researchers in the US that could eliminate the need for painful finger prick tests for people with diabetes.
According to its creators, the non-invasive biosensor can detect minute concentrations of glucose in saliva, tears and urine, offering an “inherently non-invasive way to estimate glucose content in the body.
“Because it can detect glucose in the saliva and tears, it’s a platform that might eventually help to eliminate or reduce the frequency of using pinpricks for diabetes testing. We are proving its functionality,” said Jonathan Clausse, a research scientist at the US Naval Research Laboratory.
“Most sensors typically measure glucose in blood. Many in the literature aren’t able to detect glucose in tears and the saliva. What’s unique is that we can now sense in all four different human serums: the saliva, blood, tears and urine.”
The device consists of three main parts – layers of nanosheets that resemble tiny rose petals; platinum nanoparticles; and the enzyme glucose oxidase .
The edges of each petal have dangling, incomplete chemical bonds – defects where platinum nanoparticles can attach. Electrodes are formed by combining the nanosheet petals and platinum nanoparticles. The glucose oxidase then attaches to the platinum nanoparticles, converting glucose to peroxide which generates a signal on the electrode.
Clausse, who led the development project along with Purdue University doctoral student Anurag Kumar led, said the sensor can detect glucose in concentrations as low as 0.3 micromolar – the first to report such a low sensing limit – and could also be used to test for other medical conditions, in addition to diabetes.
He explained: “Because we used the enzyme glucose oxidase in this work, it’s geared for diabetes.
“But we could just swap out that enzyme with, for example, glutemate oxidase, to measure the neurotransmitter glutamate to test for Parkinson’s and Alzheimers, or ethanol oxidase to monitor alcohol levels for a breathalyzer. It’s very versatile, fast and portable.”

Get our free newsletters

Stay up to date with the latest news, research and breakthroughs.