Chitosan sponge doped with high-yield microporous carbon nanospheres for rapid hemostasis.

Rapid and effective hemostasis can immediately control blood loss and prevent fatal complications. Chitosan sponge loaded with carbon nanospheres PC-800 for rapid hemostasis was first reported here. Preparation process is simple, green and low-cost. Specifically, microporous carbon nanospheres (PC-800) were synthesized by hydrothermal method and followed by calcination in high yield. Afterwards, PC-800 was homogeneously dispersed in the chitosan solution and lyophilized to obtain the composite sponge. The aim of this study is to explore the synergistic hemostatic effect of chitosan and PC-800 and validate its feasibility in trauma therapy. The composite sponges exhibited porous structure, suitable mechanical properties, strong water absorption capacity (49.2 ± 0.8 g/g), good hemocompatibility (hemolysis rate<5 %) and low cytotoxicity. However, cytotoxicity occurs with excessive PC-800 loads. The blood coagulation index of CS-1.0 with 9.5 % was significantly lower than the commercially available Celox Rapid. Upon application to a wound, CS-1.0 sponge rapidly forms a wound seal, achieving effective hemostasis through the synergistic action of chitosan and PC-800. Compared to Celox Rapid, tail hemorrhage and hepatic hemorrhage time in rats decreased to 73 s and 34 s, respectively. The composite sponges were expected to be a safe and fast hemostatic dressing for uncontrolled bleeding during emergencies.