Multifunctional Wide‐Temperature Threshold Conductive Eutectic Hydrogel Sensor for Shoulder Pain Monitoring and Photothermal Therapy

Abstract Conductive hydrogel‐based wearable devices have attracted significant attention for seamless human integration in health monitoring, diagnosis, and human‐machine interaction. However, achieving multifunctional epidermal electronics with self‐healing, wide‐temperature tolerance, and therapeutic capabilities remains challenging. This study presents a PVA‐PAA‐PDA‐DES eutectic hydrogel fabricated via one‐pot synthesis, demonstrating 1040% stretchability, tissue adhesion, and high ionic conductivity (1.34 S·m ⁻¹ ). The hydrogel exhibits exceptional anti‐freezing (−40 °C, 0.14 S·m ⁻¹ ) and moisture retention (>0.5 S·m ⁻¹ after 30 days) through eutectic network formation. Integrated with AI, it enables precise motion sensing and information transmission, such as with the mobile phone keypad input method for individuals with hearing impairments or speech disorders. Moreover, the system achieves accurate scapulohumeral periarthritis monitoring and timely on‐demand thermotherapy, realizing closed‐loop pain management. This work highlights the significant potential of eutectic hydrogel‐based electronic skin, such as PVA‐PAA‐PDA‐DES, in next‐generation wide‐temperature range smart healthcare and information transmission applications.