Flexible Electrochemical Sensors and Their Applications in Noninvasive Medical Detection^★

Abstract

Electrochemical sensors are widely employed for the detection of substance concentrations owing to their rapid response, high sensitivity, remarkable selectivity, and ease of quantification. With the rapid advancements in flexible electronics technology, electrochemical sensors have been transitioned into flexible and wearable formats, facilitating the in-situ analysis of biological liquids or gases. This breakthrough has opened avenues for portable, noninvasive continuous monitoring of physiological parameters and health status, thereby unveiling vast potential in the realm of intelligent healthcare and medical applications. Building upon these remarkable progressions, this paper primarily focuses on the design and applications of flexible electrochemical sensors tailored specifically for noninvasive medical detection. Firstly, the basic components of flexible electrochemical sensors are elucidated. Subsequently, the working principles of various types of sensors are expounded upon. Furthermore, we systematically review the latest advancements in the detection of pivotal chemical substances in typical biofluids such as sweat, interstitial fluid, tears, saliva, and breath, using flexible electrochemical sensors. Finally, the challenges and opportunities of flexible electrochemical sensors for applications in noninvasive health monitoring and precision medicine are discussed and proposed.