Porous SiO₂/ZnO-carboxymethyl cellulose composite hydrogels for enhanced hemostatic efficacy and antibacterial...

The development of effective hemostatic and antibacterial dressings remains a critical challenge in wound management. We report the design and fabrication of novel porous composite hydrogels composed of carboxymethyl cellulose (CMC), silica (SiO₂), and zinc oxide nanoparticles (ZnO NPs). The incorporation of SiO₂ and ZnO NPs into the CMC hydrogel matrix resulted in a unique multi-scale porous structure, characterized by interconnected holes of various sizes, which significantly enhanced the hydrogel's liquid absorption capacity and mechanical strength. The uniform dispersion of ZnO NPs throughout the porous scaffold imparted potent antibacterial activity against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. In vitro blood clotting assays shown that the SiO₂/ZnO-CMC composite hydrogel shown a significantly accelerated hemostatic effect, and the clotting time was 98 ± 18 s. This enhanced hemostasis can be attributed to the porous structure, which facilitated red blood cells (RBCs) adhesion and activation, and the synergistic action of SiO₂ and ZnO. Furthermore, the biocompatibility of the composite hydrogels was confirmed by cell viability assays, demonstrating non-toxicity to fibroblasts. These results indicate that these novel porous SiO₂/ZnO-CMC composite hydrogels hold considerable promise as a versatile material for rapid hemostasis and effective prevention of wound infections.