Skin-Interfaced Wearable Sensor for Long-Term Reliable Monitoring of Uric Acid and pH in Sweat

Abstract

Wearable sweat sensors offering real-time monitoring of biomarker levels suffer from stability and accuracy issues, primarily due to low biomarker concentrations, fluctuating sweat pH, and material detachment from sensor deformation. Here, we developed a wearable sensing system integrated with two advanced electrodes and a flexible microchannel for long-term reliable monitoring of sweat pH and uric acid (UA). By printing the ink doped with nanomaterials (Co 3 O 4 @CuCo 2 O 4 and polyaniline), we achieved highly stable electrodes for the direct analysis of perspiration, without additional surface modification. Additionally, real-time pH analysis provided a means for sensitivity calibration, reducing the effect of individual metabolism and exercise intensity. As a result, the wearable sensing system for effective gout management was validated by accurately tracking the UA fluctuations in serum and sweat of hyperuricemia patients and healthy individuals. These findings offer a reliable method for tracking biomarkers to assess personal health.