Fully Integrated Janus Textile with Enhanced Skin Comfortability for Autonomous Sweat Extraction and Analysis

Wearable sweat sensors have demonstrated tremendous potential in personalized health management and early disease diagnosis owing to their ability to noninvasively detect biomarkers. In this study, we present a fully integrated Janus-assisted sweat analysis platform that consists of a Janus textile with asymmetric wettability, an iontophoresis module for sweat generation and multiplexed electrochemical sensors. The Janus silk with asymmetric wettability can directionally transport the sweat induced by iontophoresis, which enhances sweat collection and drainage efficiency (from 53 to 72 μL) and preserves skin dryness. Compared with commercial iontophoresis sweat stimulation devices, this platform harnesses the active moisture-wicking properties of Janus textiles to address epidermal overhydration and wet adhesion caused by iontophoretic sweating, thereby significantly enhancing wearing comfort (Visual analogue scale (VAS) score 3.6 vs 7.7). Carbon nanotube fibers are integrated into Janus silk to achieve flexible and reliable electrochemical sensing of multiple physiological biomarkers. The platform maintains a dry, low-adhesion epidermal microclimate and minimizes irritation, while providing reliable, multichannel real-time biochemical monitoring, offering significant potential for personalized medicine, fitness tracking, and clinical diagnostics.