Flexible and wireless graphene-based electrochemical mHealth system towards wearable stress monitoring

Abstract

Prompt and accurate assessment of stress is crucial to human performance anal. and mental health monitoring. To avoid stress-inducing blood sampling and to realize continuous, non-invasive, and real-time stress anal. at the mol. levels, we developed an integrated wireless electrochem. sensing device based on laser-engraved graphene that are mass producible at low cost. Cortisol detection is enabled by a flexible sensor array that can conformably laminate on skin and exploits the exceptional performance and 3D porous network of laser-engraved graphene for sensitive and selective immunosensing. We report a strong correlation between sweat and circulating cortisol and demonstrate the prompt detn. of sweat cortisol variation in response to acute stress stimuli. Moreover, we demonstrate, for the first time, the diurnal cycle and stress-response profile of sweat cortisol, revealing the potential of dynamic stress monitoring enabled by this mHealth sensing system.