A facile way to fabricate a thrombin immobilized composite sponge with dual hemostatic effects for acute hemorrhage control

Uncontrolled bleeding and excessive blood loss stand as the leading causes of death in complex surgeries, civilian traumas, and military operations. Sponges have been used for developing efficiency hemostats, but most commonly used hemostatic sponges possess only one single coagulation mechanism or lack inherent blood clotting ability. Herein, we proposed simple yet innovative approaches for creating novel hemostatic composite sponges with dual hemostatic effects. Bacterial cellulose (BC) was first introduced into polyvinyl alcohol (PVA) matrix to develop a BC/PVA (CP) sponge featuring a unique cellulose-embedded porous network structure and desirable properties. Subsequently, thrombin was immobilized on CP through an easy method that combines physical adsorption and covalent binding to fabricate thrombin-carrying CP (TCP) composite sponges. The resulting composites boasted a highly porous structure, outstanding liquid-absorption capacity, low hemolysis rate, and superior biocompatibility. In vitro clotting tests revealed that TCP displayed potent coagulation capabilities, a rapid blood absorption rate, and the ability to stimulate and activate blood components along with the coagulation cascade. In vivo hemostatic assessments further confirmed that TCP offered high hemostatic efficiency and multifaceted hemostatic effects, making it suitable for the management of acute and severe bleeding.