Measurement Compensation Method for Wearable Microfluidic Sweat Sensors Toward Monitoring a Wide Range of Local Sweat Rates and Electrolyte Concentration

This letter aimed to develop and investigate a compensation method for measurement errors in sweat sensors that can simultaneously measure local sweat rates and electrolyte concentrations. The measurement error at low perspiration rates is a significant issue in these sensors, and a previous study reported large measurement errors at low sweat rate levels. The proposed method focuses on the evaporation during the sensing process and corrects the measured values by considering evaporation. The experimental results showed that the proposed method could reduce measurement errors to less than 10%, even at low sweat rate levels (under 1.0 µL/min), where significant measurement errors were observed in the previous study. These results shed light on the improvement of sweat sensors as a tool for understanding dehydration symptoms. The proposed compensation method can be used to enhance the accuracy of sweat sensors, especially in applications that require precise measurements of sweat rates and electrolyte concentrations, such as sports science, healthcare, and medical research.