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The Cortisol Challenge

Keeping all this in mind, the scientists


have developed a flexible, tiny, wearable sensor that measures cortisol levels through the sweat. The majority of the biosensors work by measuring the positive and negative charges of the molecules. But cortisol has no charge and is a major obstacle to measure its levels. So, the scientists designed a flexible patch with a cortisol sensitive membrane. The patch is waterproof and has holes in the bottom.

How they overcome the cortisol obstacle?

The sweat passes passively through the patch and the charged molecules like sodium and potassium are sent out of the membrane. Only the cortisol molecules are retained in the membrane. Then if you connect the patch to a device, it would give the results in seconds. However there is a catch, the membrane doesn’t function if it is saturated with the sweat.

Validation of the sensor









To test the accuracy of the results, the team recruited two volunteers and let them run for 20 minutes with the patches tied to their arms. The lab tests and real-world tests are quite similar indicating the reliability of the patch. The prototype patch also worked multiple times unless it is saturated with sweat. The researchers are now looking to measure the cortisol levels via saliva so that the patients no longer needed to sweat. Further, the team hopes to measure multiple biomarkers at a time which would offer a clearer picture of what’s going inside the body.

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