As more and more people find themselves diagnosed with diabetes, it is clear that blood glucose sampling with needle pricks is a significant burden on the patient population. That can all change if someone comes up with a better way of finding out a person’s glucose levels.
Researchers at Purdue University may have actually come up with a possible solution that may allow diabetics of the future to use their saliva, tears, or even urine to measure their glucose. The team developed a new sensor that can be cheap to build and that can detect glucose in any of the body’s serums. It is based on petal shaped sheets of stacked graphene that have glucose oxidase enzyme and platinum nanoparticles deposited on its surface. As glucose converts to hydrogen peroxide, a signal is generated at the electrodes where the platinum particles are.
Though the technology is promising, a challenge remains of correlating saliva or tear glucose levels to those in blood found in the same person.
From the press release:
“Because we used the enzyme glucose oxidase in this work, it’s geared for diabetes,” [Jonathan Claussen, one of the study’s lead authors,] said. “But we could just swap out that enzyme with, for example, glutemate oxidase, to measure the neurotransmitter glutamate to test for Parkinson’s and Alzheimer’s, or ethanol oxidase to monitor alcohol levels for a breathalyzer. It’s very versatile, fast and portable.”
The technology is able to detect glucose in concentrations as low as 0.3 micromolar, far more sensitive than other electrochemical biosensors based on graphene or graphite, carbon nanotubes and metallic nanoparticles, Claussen said
“These are the first findings to report such a low sensing limit and, at the same time, such a wide sensing range,” he said.
The sensor is able to distinguish between glucose and signals from other compounds that often cause interference in sensors: uric acid, ascorbic acid and acetaminophen, which are commonly found in the blood. Unlike glucose, those compounds are said to be electroactive, which means they generate an electrical signal without the presence of an enzyme.
More from Purdue: Sensor detects glucose in saliva and tears for diabetes testing
Abstract in Advanced Functional Materials: Biosensors: Nanostructuring Platinum Nanoparticles on Multilayered Graphene Petal Nanosheets for Electrochemical Biosensing