- New biosensor-equipped eyeglasses can measure glucose levels through a person’s tears.
- The process is safe and painless.
- The device could also measure vitamin and alcohol levels in the blood.
In the recent decade, wearable devices have created an immense commercial interest, which has stimulated considerable efforts towards the advancement of wearable and mobile sensing systems.
While physical sensors and wearable mobility got a lot of early attention, the recent trend has been shifted to the development of devices that can detect (bio)chemical markers.
Wearable chemical sensors have already been integrated into several platforms including temporary tattoos, mouthguards, textiles, and wristbands. Now scientists at the University of California and the University of Sao Paulo (Brazil) have taken things one step further: they developed a novel biosensor that can measure glucose levels through a person’s tears.
How Does It Work?
It identifies the glucose oxidase enzyme — mostly used to detect free glucose in body fluids — in tears. Human tears contain a variety of metabolites and by measuring their concentrations, one can reveal concurrent blood levels.
Researchers mounted a fluidic device onto the eyeglasses nose-bridge pad to enable the direct collection of stimulated tears.
Tears are produced through the lachrymal gland and as soon as tears come into contact with the glucose oxidase, the flow of electron is altered. This generates a signal that is processed by a chip integrated into the arm of eyeglasses. The results are instantly sent to a smartphone or computer so patients can monitor their diabetes in real-time.
Reference: ScienceDirect | DOI:10.1016/j.bios.2019.04.058 | SciDev
This is the first device that allows real-time tear collection and direct alcohol measurements in stimulated tears. Users can integrate the wireless electronic circuit into any frame, making a completely-portable, easy-to-use fashionable sensing device.
Biosensor-equipped eyeglasses | Credit: Juliane Sempionatto Moreto
At present, most people use a portable glycosometer that measures blood glucose levels. This involves pricking fingertips several times a day (to get blood samples), which is a painful and unsafe process as the needle increases the risk of infection.
The new technology, on the other hand, is both safe and painless. The device could also measure vitamin and alcohol levels in the blood by simply altering the coupled electrodes connected to the nose pads.
Researchers believe that such devices can diagnose and prevent neglected diseases in rural areas. In fact, the technology could be used to diagnose genetic disorders shortly after or even before birth.
Still A Long Way To Go
Further studies are needed to make the system more accurate. It is also necessary to gain detailed insights into the effect of the tear stimulation and collection upon the analyte concentration.
Read: Vision-Enhancing Nanodrops Could Replace Eyeglasses
The research team will try to commercialize the technology within 3 years. However, they are not sure about when biosensor-equipped glasses will hit the market.
