A comprehensive review on electrochemical cytokine detection in sweat

Cytokines are signaling proteins present in human fluids. Their detection is crucial in understanding immune system activity and supporting the diagnosis and monitoring of diseases such as sepsis, diabetes, and cancers. Nevertheless, investigating temporal profiles of these crucial biomarkers still relies on blood sampling (potentially uncomfortable for patients and only providing a snapshot) and laboratory analysis. Wearable electrochemical sensors represent next-generation diagnostic and health monitoring methodologies, effectively investigating biomarkers in a continuous manner in alternative body fluids (e.g., sweat), thereby holding potential for early disease detection and enabling remote and enhanced personalized health monitoring. This work comprehensively reviews the significant potential of continuous electrochemical detection of cytokines in sweat. First, an overview of the role of cytokines from a medical perspective is given. Then, the concept of electrochemical sensors is introduced and the current state of the art of electrochemical sensing of cytokines in sweat toward wearable applications is critically assessed.