High-strength anti-bacterial composite cryogel for lethal noncompressible hemorrhage hemostasis: Synergistic physical hemostasis and chemical hemostasis

Porous cryogel with its poor mechanical properties greatly limit its application for lethal non-compressible bleeding from deep wounds. Here, we creatively combined foaming reaction and cryo-polymerization reaction to prepare a series of high-strength composite cryogel hemostatic agents based on Poly(vinyl alcohol) (PVA), Carboxymethyl chitosan (CMCS) and Dopamine (DA) to cope with lethal noncompressible bleeding. The optimized PVA/CMCS-DA6 cryogel (1 mL prepolymer solution contains 6 mg DA) exhibited compression stress higher than 125 kPa at 80% compression strain and tensile stress-at-break higher than 155 kPa which are much higher than that of traditional cryogels. The hemostatic material with shape memory behavior and high compression strength can effectively stop lethal non-compressible bleeding, which has a good physical hemostatic effect, and the hemostat is easy to be removed after hemostasis. In addition, PVA/CMCS-DA6 cryogel showed better whole blood clotting ability, platelets and blood cells activation ability than commercial gelatin sponge and medical gauze, which has a good chemical hemostatic effect. PVA/CMCS-DA6 cryogel with synergistic chemical hemostasis and physical hemostasis showed outstanding hemostatic capacity in the rabbit liver defect non-compressible hemorrhage model and lethal coagulopathic rabbit liver defect bleeding model. Therefore, high-strength PVA/CMCS-DA cryogels have great potential as a new hemostatic agent for controlling lethal bleeding and providing a new idea for the design of efficient hemostatic materials.