A Breathable Nanofibrous Wearable Sweat Sensor for Simultaneous Monitoring of pH and Uric Acid

Wearable sweat analytics require sensors that are simultaneously chemically selective, mechanically conformal, and highly breathable. Here, we report a flexible electrochemical platform that integrates a polyaniline‐modified gold electrode for pH detection with a laser‐reduced graphene oxide electrode for uric acid sensing on a thermoplastic polyurethane nanofiber membrane. The porous substrate (59.5 mm/s air permeability; 2716.6 g/m 2 ·24 h water vapor transmission rate) sustains skin comfort while minimizing sweat‐induced drift. The device delivers a near‐Nernstian pH response (59.98 mV/pH, pH 4–8) and a linear uric acid signal (50–500 µM) with strong anti‐interference capability; on‐body tests show <6% deviation from a commercial pH meter and stable dual‐analyte readouts during 8 h of activity. The device architecture offers an extensible platform for noninvasive, real‐time biochemical monitoring in personal health, athletics, and disease prevention.