A Dual‐Crosslinked Collagen/Oxidized Cellulose Composite Sponge Synergistically Constructed via Polyelectrolyte Complexation for Efficient Emergency Hemostasis

ABSTRACT The development of effective hemostatic materials for acute hemorrhage control remains a significant clinical challenge. This study presents a dual‐crosslinked hemostatic sponge fabricated by modifying collagen (COL) with dialdehyde oxidized cellulose (DOC) of varying carboxyl contents. The material design leverages synergistic mechanisms involving Schiff base formation and polyelectrolyte complexation. The resulting dual‐crosslinked network demonstrated exceptional fluid absorption capacity, reaching 3000% and 5000% of its dry weight in water and blood, respectively, within 5 min, while maintaining excellent structural integrity without significant shrinkage or deformation. This property ensures optimal wound contact during application. Notably, the DOC‐COL‐18.90% composite sponge (using DOC with 18.90% carboxyl content) reached 1.9 times the compressive modulus of the pure COL sponge. In vivo evaluations revealed superior hemostatic performance, with blood loss measuring 187 ± 8 mg and hemostasis time of 65 ± 7 s in liver injury models, significantly lower than those of the commercial hemostatic agent Gelfoam, which showed 682 ± 15 mg blood loss and 112 ± 11 s hemostasis time. The optimized composite sponge also exhibits excellent hydrophilicity, thermal stability, and biocompatibility, demonstrating strong potential for clinical application in acute hemorrhage management.