Advanced smartwatch for noninvasive sweat biomarker monitoring using a wearable FET biosensor array with Ag nanowire...

This study introduces the development of a next-generation wearable biosensor for non-invasive glucose monitoring in human sweat, leveraging the unique properties of advanced two-dimensional (2D) nanomaterials. Central to this innovation is a smartwatch-based platform designed for real-time health monitoring. The research focuses on three distinct field-effect transistor (FET) configurations, each utilizing a copper electrode array as the source, drain, and gate, and different 2D composite materials as the transistor channel. The FET channels were fabricated using a hydrothermal synthesis method to produce four high-performance composites: silver nanowires/Ti₃C₂ MXene, Ti₃C₂ MXene/MoS₂, AgNWs/MoS₂. and a ternary combination of MoS₂/Ti₃C₂ MXene/silver nanowires. Each material contributes unique advantages-silver nanowires provide high electrical conductivity for efficient charge transport, MoS₂ provides abundant active sites for glucose oxidation, and Ti₃C₂ MXene enhances both electrical conductivity and surface functionalization, facilitating improved glucose detection. In addition to glucose sensing, the developed smartwatch can simultaneously monitor pH and temperature, factors that are critical for accurate biosensing in sweat. Comprehensive material analysis, fabrication methods, and performance evaluations are detailed in this work. The proposed Bio-FET sensors demonstrate outstanding performance metrics, including an ultra-low detectable concentration of 0.001 µM, a sensitivity of 355 mA·mM⁻¹, and a broad span of linear detection from 0 to 10 mM. The sensors also exhibit excellent repeatability, reproducibility, and long-term stability.