Lab on a Contact Lens Can Measure Stress Through Serotonin

Automated excerpt

As such, the scientists explored whether tears might offer a noninvasive, easily accessible route to analyze serotonin levels. The lenses could detect as little as 72-trillionths of a mole per liter of serotonin, well below the average serotonin concentration in human tears of roughly 15-billionths of a mole per liter. The lens could detect serotonin when the eye was given artificial tears containing 50 and 100 nanomolar levels of the hormone.

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