Bioinspired bioactive bilayer membrane: A biodegradable adhesive membrane integrating hemostasis, antibacterial, and anti-adhesion functions for visceral repair

Current soft tissue repair membranes have insufficient wet adhesion, postoperative adhesion risk, and limited therapeutic functionality. Therefore, we adopted a multiscale biomimetic design using mussel adhesion chemistry and the interfacial robustness of 3,4,5-trihydroxyphenylalanine (TOPA) in the tunicate epidermis to construct a biodegradable bilayer hydrogel membrane (PLCL-CSs@PADT). This design enables interfacial water displacement, robust tissue adhesion (21 kPa strength, 110 J m −2 fracture energy), antibacterial hemostasis (>80%), and a topological hydrophobic barrier for adhesion prevention. Methacrylated gelatin is introduced as a photocurable interfacial bridging phase, achieving seamless mechanical continuity, while gradient cyclic elution eliminates residual monomers. The membrane rapidly achieved hemostasis in rat hepatic hemorrhage models (<20 s) and reduced blood loss by 83%. In postoperative abdominal adhesion models, the material completely prevented adhesion formation, attributed to the combined shielding effect of the outer layer and regulation of t-PA/PAI-1 expression. In vitro experiments demonstrated that the membrane exhibits a preliminary trend of controlled biodegradation over an 8-week period, aligning with typical soft-tissue healing timelines. This work establishes a multifunctional, bioinspired platform that combines instant tissue sealing, infectious risk mitigation, and sustained anti-adhesion performance and contributes to the development of next-generation intelligent bioactive membranes for complex soft-tissue repair.