An ultrasensitive and wearable photoelectrochemical sensor for unbiased and accurate monitoring of sweat glucose

Wearable electrochemical sensors have been extensively used for the non-invasive and quantitative on-body detection of biomarkers in sweat. However, the photoelectrochemical (PEC) sensor, which is an evolutionary generation of the electrochemical method and holds higher sensitivity and the ability to unbiased analysis, is rarely applied to construct flexible wearable sweat devices. Herein, we demonstrated a flexible PEC patch comprised of an ultrasensitive PEC sensor and a hydrophilic poly-(dimethylsiloxane) sweat collector for unbiased and high-performance sweat glucose detection. The proposed PEC sensor offered excellent durability against mechanical deformations, low detection limit (22.2 pM), desirable selectivity, and high storage stability. Moreover, the feasibility and accuracy of this wearable glucose sensor patch were validated through human subjects studies, and the obtained sweat glucose test results closely matched with the commercial kit and correlated well with the blood glucose level. Taken together, we could confirm the considerable promise of the unbiased wearable PEC sensor for patient-friendly diabetic diagnosis.