Hemostatic Sponge Based on Modified Alginate and Water-Soluble Chitosan for Rapid Hemorrhage Control

Hemorrhage remains a leading cause of preventable mortality in trauma and surgical settings, necessitating hemostatic materials that act rapidly while maintaining mechanical integrity and safety. Here, we report a flexible hemostatic sponge composed of 2-(dimethylamino)ethyl methacrylate (DMAEMA)-modified water-soluble chitosan and dual-functionalized alginate derivatives (alendronate- and 3-(dimethylamino)-1-propylamine (DMPA)-modified alginate). The materials were synthesized entirely in aqueous media and processed via controlled freezing followed by freeze-drying, yielding partially ionically cross-linked porous scaffolds (∼85% porosity) with rapid swelling (up to ∼4500% within 10 min) and efficient blood absorption. Structural characterization confirmed successful functionalization, while the scaffolds exhibited tensile strengths of 260–290 kPa and maintained structural integrity under physiological conditions for up to 2 weeks. The sponges demonstrated low hemolysis (<8%) and high fibroblast viability (>95%), indicating good hemocompatibility and cytocompatibility. In a mouse liver hemorrhage model, the material significantly reduced blood loss (84.3%) and exhibited hemostatic performance comparable to the commercial control KALTOSTAT. This dual-modification strategy integrates a Ca²⁺-mediated coagulation support, rapid fluid absorption, and cationic blood-material interactions, enabling effective bleeding control while maintaining structural durability. These findings highlight the potential of the WS-C/MA sponge for emergency and surgical hemostasis.