Next-generation wearable electrochemical sensors for personalized healthcare

Growing healthcare demands, advancements in flexible electronics, and the development of digital health technologies have made wearable sensors essential tools for continuous, noninvasive health monitoring. These sensors provide up new avenues for early diagnosis and individualized treatment by enabling continuous monitoring of physiological and biochemical information. This critical review provides a comprehensive evaluation of recent advances in wearable electrochemical sensors, with emphasis on sensor construction, functional materials, sensing principles, biofluid selection, artificial intelligence (AI), Internet of Things (IoT) integration, and emerging trends, while critically discussing current limitations and future opportunities. This review first introduces the basic components, advanced materials, fabrication methods and working principles, covering electrochemical, piezoelectric, triboelectric, capacitive, piezoresistive, optical, and magnetic sensing approaches. Next the wearable systems for biofluid analysis, including sweat, interstitial fluid, saliva, and tears, which enable noninvasive biochemical intelligent health monitoring are discussed. The review also highlights the role of AI and machine learning in data interpretation, along with wireless communication and IoT technologies for real-time applications. The latest developments in wearable electrochemical sensors-including advanced techniques, closed-loop systems, multimodal sensor integration, and self-powered sources are further explored. Lastly, prospective directions for next-generation wearable sensing systems in healthcare are discussed, along with present issues with reliability, long-term stability, data management, and widespread adoption.