Highly stable and selective flexible sweat sensor combined with bioinspired microfluidic chip: Zn-Ni bimetallic...

To enable non-invasive, dynamic renal function monitoring, this study pioneered a flexible wearable platform integrating high-sensitivity sensing materials and an efficient sweat transport system. A flexible creatinine sensor (CrS) was fabricated with Zn-Ni bimetallic MOF (Ni/Zn = 3:1), COOH-CNT, and LIG interdigitated electrodes, followed by PDMS encapsulation. It exhibited superior electrochemical performance in the 0.08-1 mmol/L creatinine range, with R² values of 0.978 (0.08-0.5 mmol/L) and 0.979 (0.5-1 mmol/L), a sensitivity of 283.3 μA/(mmol·cm²), excellent anti-interference ability, and robust stability under bending, physiological temperature, and long-term storage. Inspired by the Texas horned lizard's skin microstructure, a biomimetic microfluidic chip with asymmetric microgroove arrays was prepared via 3D printing and PDMS replica molding, achieving a 0° contact angle after plasma treatment. At optimal parameters, liquid droplets realized spontaneous directional transport at 9.7 mm/s, with integrated capillary burst valves preventing cross-contamination. Human sweat spiking experiments verified the platform's reliability in real biological matrices. This non-invasive, portable platform first achieves "efficient transport-precise detection" synergy, providing a novel technical strategy for early chronic kidney disease screening with high translational potential.