A Flexible Wearable System for Integrated Sweat Stimulation and Chloride Analysis in Cystic Fibrosis Diagnosis

Cystic Fibrosis diagnosis relies on qualitative sweat chloride testing, which is limited to trained personnel, bulky instrumentation, cumbersome workflow at specialized clinical centers with high per-test cost. Recent advances in wearable sweat biomarker sensors offer opportunities in development of point-of-care CF sweat chloride analysis. This work presents a flexible, wearable platform for CF sweat chloride testing, based on miniaturized, automated iontophoresis stimulation, microfluidic sweat collection, and colorimetric chloride analysis. This system enables quantitative, visually interpretable chloride measurements without external instrumentation, requires a considerably smaller volume of sweat to operate, and reduces the per-test cost to around 1 dollar. Clinical validation of the device with over 50 subjects, spanning a board age range, demonstrates strong agreement with standard clinical sweat testing protocol and reliable operation across physiologically relevant chloride concentrations. This platform provides a practical, scalable alternative for cystic fibrosis diagnostics in both clinical and resource-limited settings.