Bioinspired Heterogeneous Wettability Triboelectric Sensors for Sweat Collection and Monitoring

Triboelectric sweat sensors, endowed with the technical advantages of non-invasive ex vivo and in situ detection, have catalyzed the rapid advancement of personalized medicine and precision health management systems. However, the inherently low secretion rate and rapid evaporation of sweat pose significant challenges for its efficient collection and rapid analytical screening. This study leverages laser cutting and aqueous interfacial self-assembly strategies to develop a biomimetic heterogeneous wettability triboelectric material (HWTM). Sweat is rapidly collected from the edge to the center of the material, driven by the combined effect of a wettability gradient and the Laplace pressure difference arising from asymmetric curvature at the liquid-solid interface. This collection mechanism markedly enriches target analytes, yielding a signal-to-noise ratio (SNR) of 51 dB, which surpasses that of prevailing sweat sensor technologies. A portable wearable patch is engineered by integrating ion-selective membranes and data processing modules, enabling selective salt ion profiling and real-time wireless monitoring. This work paves the way for the rational design of sweat sensors grounded in fluidic transport mechanisms.