Construction of Nanoparticle-Enhanced Multimodular Hemostatic Sponges and Their Application in Multiple Bleeding Scenarios

Chitosan-based (CS-based) materials have attracted considerable attention owing to their excellent biocompatibility and intrinsic hemostatic activity, rendering them promising candidates for emergency hemorrhage control. Nevertheless, their clinical performance is often constrained by inadequate wettability and limited mechanical strength. In this study, we developed a superelastic hemostatic sponge (HMCT-NP) through a facile freeze-drying approach by incorporating hydrophobically modified CS, tannic acid (TA)-mediated cross-linking, and functional Fe-baicalin nanoparticles (Fe-Ba NPs). The grafted hydrophobic alkyl chains can insert into the membranes of red blood cells (RBCs) and platelets, thereby promoting their active adhesion and aggregation to accelerate rapid coagulation. TA enhances the mechanical properties of the sponge via hydrogen-bond-mediated cross-linking while also providing antibacterial and antioxidant functionalities. The incorporation of nanoparticles enhanced the antibacterial and antioxidant properties of the sponge and, notably, led to a significant improvement in its mechanical robustness. Through this modular design and synergistic functional enhancement, HMCT-NP effectively mitigates the intrinsic poor wettability of CS-based hemostatic sponges, demonstrating a water uptake capacity of approximately 95 g/g and a volumetric expansion greater than 200% upon hydration, thereby enabling rapid fluid imbibition and enhancing blood cell aggregation at the bleeding interface. Furthermore, its high compressibility and rapid fluid-triggered shape recovery enable effective deployment in narrow or deep wounds while maintaining biosafety and minimizing tissue irritation. In various bleeding models, HMCT-NP sponge demonstrated enhanced procoagulant activity and hemostatic performance. Meanwhile, the sponge effectively accelerated the healing of infected wounds. Collectively, these results underscore the potential of the HMCT-NP sponge as a versatile and promising strategy for clinical hemorrhage management.