Wearable sweat-sensing patches for non-invasive and continuous health tracking

• The sweat-sensing mechanisms and performance of patch-based sensors. • The design and fabrication strategies of sweat patch sensors. • Role and importance of patches in sweat sensing. • The applications of sweat patch sensors in numerous fields. • Existing challenges and future opportunities for sweat-based sensors. The demand for biosensing systems that accurately detect physiological signals and disease biomarkers while maintaining biocompatible surfaces drives ongoing research into advanced materials and novel designs. Wearable patch-based sensors have emerged as a promising solution for effective sweat management, offering easy induction, reliable collection, and precise analysis. This review systematically explores recent advancements in wearable sweat-sensing patches (WSPs) for personalized healthcare monitoring, highlighting their value in non-invasive and continuous health tracking. While recent reviews on wearable sweat sensing have provided general overviews of sweat sensing technologies, this review focuses on the integration of WSPs with emerging fields like flexible human-machine interfaces and smart healthcare solutions, addressing specific technical challenges and innovative approaches that distinguish current advancements. It provides a thorough analysis of key components, including structural materials, sensing mechanisms, innovative sweat collection techniques, and optimal attachment strategies. Additionally, the review addresses challenges and emerging trends, offering a pathway for integrating WSPs into flexible human-machine interfaces, personalized healthcare solutions, and closed-loop systems. Wearable Sweat-Sensing Patches for Non-Invasive and Continuous Health Tracking.