Monolithic tissue sealant membrane with covalently‑anchored NHS‑activated gelatin adhesive moieties on flexible PLCL substrate: preparation, characterization and biological performance

Clinically available tissue sealant membranes are limited by high swelling, poor flexibility, insufficient adhesion and high cost, restricting their use in complex surgeries. Herein, a novel monolithic embedded tissue sealant membrane (IIIb) was constructed A monolithic PLCL‑based tissue sealant membrane (IIIb) is proposed. Via UV‑initiated copolymerization, NHS‑modified gelatin adhesive segments are covalently anchored onto the substrate, which differs from the conventional physically‑laminated bilayer control (IIIa) and effectively avoids interfacial delamination.The optimized membrane achieves strong wet adhesion (8.15 KPa) and ultra-low 72 h swelling ratio of only 1.1%.Tunable degradation (4–36 weeks) is realized by adjusting PLCL dosage to match diverse soft tissue healing cycles.The membrane exhibits excellent cytocompatibility, hemocompatibility and negligible in vivo systemic toxicity.Ex vivo porcine organ defect tests confirm reliable burst pressure to meet clinical tissue sealing demands.