KAUST researchers have developed a sensor that can measure glucose levels in saliva, offering diabetics an alternative means to monitor glucose levels in their blood. Credit: © 2023 KAUST; Anastasia Serin.
Key points:
- A new prototype sensor offers a simple, rapid and noninvasive way to measure glucose levels in saliva.
- The sensor uses highly sensitive semiconductors topped with the glucose oxidase enzyme to measure current changes reflecting saliva sample glucose concentration.
- Researchers can expand their sensor development to create arrays that simultaneously detect multiple metabolites in saliva.
People with diabetes have traditionally monitored their blood glucose with devices that analyze a drop of blood from pricking a finger several times a day. Recently, implanted sensors have provided continuous glucose monitoring without unpleasant pricking, but are less accurate for lower glucose levels and are not approved for children.
Now, a new study in Biosensors and Bioelectronics proposes a prototype sensor that measures glucose levels in saliva to offer a simple, rapid and painless way to monitor diabetes.
“An easy-to-use noninvasive glucose measuring device using saliva as a medium could be life-changing for millions of patients worldwide,” explained Abhinav Sharma of King Abdullah University of Science and Technology (KAUST).
Researchers have created a highly sensitive glucose detector based on a thin-film transistor containing layers of semiconductors and topped with the enzyme glucose oxidase. When saliva is placed on the sensor, the enzyme oxidizes glucose to trigger current flow through the semiconductors. The size of the current indicates the glucose concentration of the saliva sample.
The team tested the device using saliva samples with different amounts of added glucose, as well as saliva samples from volunteers. The device correctly measured the wide range of glucose concentrations in less than a minute without any impact of other molecules in saliva—even sugar derivatives sucrose and fructose.
The device’s sensitivity declined over time, but its performance was still good after being stored for two weeks at room temperature. Importantly, the device was small, lightweight, and low-power meaning it could be suitable for mass production as an inexpensive disposable sensor.
The research group’s next steps include creating an array of transistor sensors that can simultaneously detect multiple metabolites in saliva.
“The development of portable sensor arrays that can be integrated with a smartphone is a potential future direction for research,” said Thomas Anthopoulous, who led the KAUST team.