Implantable electrochemical sensors for continuous blood monitoring

The dynamic changes in blood physicochemical properties are regarded as the most direct and immediate window into the physiological state of the body, which cannot be captured by conventional intermittent blood sampling and analysis. The emergence of implantable electrochemical sensors offers a transformative solution, enabling blood to be monitored directly, in situ, and continuously, thereby potentially shifting medical diagnosis from a standardized model based on population averages toward an era of dynamic, individualized analysis. Recent developments have focused on material design and sensing technologies, through which continuous monitoring of multiple key analytes in blood has been achieved. This review systematically examines this rapidly advancing field. The unique properties of blood and their influence on sensing strategies and device design requirements are analyzed. Subsequently, newly developed materials and advanced fabrication technologies that address these challenges are surveyed. Furthermore, recent progress in two key application scenarios, real‐time intraoperative physicochemical monitoring and long‐term pharmacokinetic studies, is highlighted. Finally, the core challenges for clinical translation are discussed, and future research directions are outlined, aiming to provide a clear roadmap for interdisciplinary collaboration and to accelerate the translation of this technology from the laboratory to the clinic.