Underwater Instant Adhesive Hydrogel Interfaces for Robust Biosensing on Diverse Species

Hydrogel-assisted soft biosensors have emerged as transformative platforms for multimodal physiological monitoring in amphibious environments. However, developing instant underwater adhesive, scalable manufacturing, and robust interfaces for long-term continuous multi-physiological bioelectronics remains challenging. Here, a universal and facile fabrication strategy is presented that overcomes these limitations through molecular entanglement engineering to fabricate instant underwater adhesion hydrogel interfaces, exhibiting rapid, strong interfacial toughness over 230 J•m⁻² within 10 s. Besides, a roll-to-roll scalable manufacturing protocol for practical transformation is established. The hydrogel interfaces with tissue-like softness ≈109 kPa, enabling seamless multimodal biosensor integration across interfaces from aquatic organisms to amphibious species and human epidermis for reusable and long-term usage, facilitating simultaneous multiparametric physiological signal acquisition and behavioral tracking. These findings establish a new design framework of molecular entanglement engineering for instant adhesive hydrogel interfaces, which enables reliable and rapid response biosensing technologies for healthcare monitoring and wildlife conservation.