A novel wearable sweat sensor, developed by researchers at the University of Texas at Dallas and in the process of being commercialized by EnLiSense, could provide insight into the health and stress levels of wearers — even if it can only sample a tiny amount of sweat.
Known as the SweatSenser, the EnLiSense wearable uses electrochemical impedance spectroscopy (EIS) to measure the cortisol levels in the wearer's sweat — and because of the sensor type in use, it's able to operate based on extremely small samples. Previously, many similar monitoring systems have been limited to use in exercise where the wearer is guaranteed to work up a sweat — making them ill-suited for round-the-clock monitoring.
In testing, the sensor — also known as the Wearable Awareness Through Continuous Hidrosis (WATCH) device - proved capable of not only tracking cortisol, which can spike both under stressful conditions and in inflammatory illnesses, but glucose levels which would typically require a blood sample instead.
The SweatSenser isn't the first to link cortisol levels to stress and to turn to a sweat-sampling wearable to monitor them: Two years ago researchers at the California Institute of Technology (Caltech) unveiled a wearable sweat sensor which operates in much the same way — though a later project by the Universities of Houston and Miami turned instead to skin conductance, rather than sweat sampling, measurable using low-cost electrodes added to a smartwatch platform.
Details on the use of the SweatSenser to pick up cortisol and glucose in sweat were published to the journal Bioengineering & Translational Medicine earlier this year under open-access terms, while an earlier article in the same journal looks at using the sensor to track infection via cytokine levels.
Additional information is available on IEEE Spectrum, which brought the gadget to our attention.