Phycocyanin/Liquid Metal Hydrogel-Based Wearable Electronics for Monitoring Physical Stimulus-Response Behavior

We present a high-performance hybrid hydrogel strain sensor based on phycocyanin (PC) and eutectic gallium–indium liquid metal (LM), designed for next-generation biocompatible wearable electronics. The hydrogel integrates a dynamic ionic coordination and hydrogen-bonded network with deformable conductive LM pathways, offering exceptional mechanical and electrical properties. It exhibits strong adhesion on biological tissue (up to 81.16 kPa on pigskin), excellent fatigue resistance (stable over 400 cycles at 100% strain), and reliable signal responsiveness. Integrated with a microcontroller, signal processor, and Bluetooth transceiver, the hydrogel sensor enables real-time monitoring of complex motions, including underwater fish movement and tactile stimuli. This multifunctional platform demonstrates strong potential for wearable bioelectronics in dynamic and aquatic environments.