21/05/2026
For many people, health monitoring has become part of daily life. That doesn’t mean it has become comfortable. Needles, blood samples, bulky devices, frequent hospital visits — many monitoring technologies still demand too much effort from the people who rely on them most.
Tear fluid is rarely seen as a source of health data. Yet it carries far more biological information than most people realize, even though concentrations are low enough that reading it accurately remains a real engineering challenge.
Glucose monitoring is one part of the picture. For the 830 million people living with diabetes, and the many more at risk, it remains invasive and uncomfortable.
Tear fluid contains glucose as well, and tear glucose has been shown to reflect blood glucose trends, with a natural physiological delay of around 10–15 minutes. We are developing a smart contact lens that reads glucose from tear fluid — the same way a home glucometer works, using electrochemical sensing.
For medications with serious side effects, knowing whether the previous dose is still active can be critical, and tear fluid can help answer that question too.
The contact lens is worn as usual and at the end of the day, is placed into a standard contact lens container: a compact reading device with a built-in spectrometer. Molecule concentrations in tear fluid are extremely low, which is why the contact lens uses proprietary gold nanoparticles to amplify the signal, so that the spectrometer can identify molecules by the way each one absorbs and reflects light.
This is only the beginning of what tear fluid can reveal. The same approach could be extended to hormones, vitamins, and other biomarkers. We believe the next generation of health technology should work more naturally with the body, rather than demand constant effort from the people using it.
