A macromolecular cross-linked alginate aerogel with excellent concentrating effect for rapid hemostasis

Alginate-based materials present promising potential for emergency hemostasis due to their excellent properties, such as procoagulant capability, biocompatibility, low immunogenicity, and cost-effectiveness. However, the inherent deficiencies in water solubility and mechanical strength pose a threat to hemostatic efficiency. Here, we innovatively developed a macromolecular cross-linked alginate aerogel based on norbornene- and thiol-functionalized alginates through a combined thiol-ene cross-linking/freeze-drying process. The resulting aerogel features an interconnected macroporous structure with remarkable water-uptake capacity (approximately 9000 % in weight ratio), contributing to efficient blood absorption, while the enhanced mechanical strength of the aerogel ensures stability and durability during the hemostatic process. Comprehensive hemostasis-relevant assays demonstrated that the aerogel possessed outstanding coagulation capability, which is attributed to the synergistic impacts on concentrating effect, platelet enrichment, and intrinsic coagulation pathway. Upon application to in vivo uncontrolled hemorrhage models of tail amputation and hepatic injury, the aerogel demonstrated significantly superior performance compared to commercial alginate hemostatic agent, yielding reductions in clotting time and blood loss of up to 80 % and 85 %, respectively. Collectively, our work illustrated that the alginate porous aerogel overcomes the deficiencies of alginate materials while exhibiting exceptional performance in hemorrhage, rendering it an appealing candidate for rapid hemostasis.