Wearable devices for health monitoring and fitness management have foreseen a rapidly expanding market, especially those for noninvasive and continuous measurements with real-time display that provide practical convenience and eliminated safety/infection risks. Herein, a self- powered and fully integrated smartwatch that consists of flexible photovoltaic cells and rechargeable batteries in form of a “watch strap”, electrochemical glucose sensors, customized circuits and display units integrated into a “dial” platform, is successfully fabricated for real-time and continuously monitoring of sweat glucose levels. The functionality of the smartwatch, including sweat glucose sensing, signal processing and display, can be supported with the harvested/converted solar energy without external charging devices. The Zn-MnO2 batteries serve as intermediate energy storage units and the utilization of aqueous electrolytes eliminated safety concerns for batteries, which is critical for wearable devices. Such a wearable system in a smartwatch fashion realizes integration of energy modules with self-powered capability, electrochemical sensors for noninvasive glucose monitoring, in situ and real-time signals processing/display in a single platform for the first time. The as-fabricated fully integrated and self-powered smartwatch also provides a promising protocol for statistical study and clinical investigation to reveal correlations between sweat compositions and human body dynamics.
Project end date: 01/29/20