Recent advances and challenges in electrochemical sweat potassium ion sensing for sports and health monitoring: a review

Purpose This study aims to provide a critical and comprehensive assessment of the latest advancements and remaining challenges in the development of electrochemical potassium ion (K+) sensors for sweat analysis, with particular emphasis on applications in sports performance monitoring and general health assessment. Design/methodology/approach The review systematically explores the physiological relevance of K+ in sweat, its utility in different application contexts (athletic vs clinical) and the underlying principles of potentiometric solid-contact ion-selective electrodes. It evaluates the evolution of solid-contact materials from conducting polymers to carbon nanomaterials and MXenes, alongside fabrication techniques and integration strategies for multiplexed sensing platforms. Furthermore, it identifies technical obstacles – such as signal drift, on-body calibration and lack of clinical validation – and discusses current research directions to address them. Findings Advanced SC materials such as MXenes and carbon nanomaterials significantly improve potential stability and sensing performance compared to traditional conducting polymers. Multiplexed wearable systems that combine K+ sensing with other biomarkers (e.g. Na+, pH and temperature) enable more reliable and contextualized physiological data. However, in spite of progress, challenges such as long-term operational stability, sensor calibration on the body and the absence of a validated correlation between sweat and blood K+ concentrations remain major barriers to clinical translation. Originality/value This review bridges materials science, electrochemical sensing, wearable systems engineering and personalized health care. It uniquely positions sweat K+ monitoring not only as a performance optimization tool for athletes but also as a potential early-warning indicator for physiological imbalances. This study provides an interdisciplinary roadmap towards realizing autonomous, smart and clinically meaningful sweat sensors.