Development of antibacterial and superabsorbent wound composite sponges containing carboxymethyl cellulose/gelatin/Cu-doped ZnO nanoparticles

This study aimed to develop a novel antibacterial and superabsorbent dressing by introducing the Cu-doped ZnO nanoparticles into the carboxymethyl cellulose/gelatin glutaraldehyde-crosslinked composite sponge that is fabricated by lyophilization method. Undoped and Cu-doped ZnO (Zn1−xCuxO, x = 0.03 and 0.05) nanoparticles were synthesized through the stabilizing agent-used precipitation process and characterized by XRD, FESEM, FTIR, and ICP-OES techniques. The XRD evaluation determined that the concentration of copper in ZnO is limited to below 5%. Additionally, The ICP-OES analysis confirmed the effect of the doping process on the ZnO crystalline structure by releasing more zinc and copper ions from Cu-doped ZnO, which resulted to improve antibacterial activity against Staphylococcus aureus and Escherichia coli bacterial strains. The effect of ZnO nanoparticles on the physical and mechanical performance of the optimized composite sponge indicated that the incorporation of 3 wt% ZnO nanoparticles produces a well-interconnected porous structure (~156 µm) with high water absorption (~3089%) and proper elongation (~49%) in a wet medium. The incorporation of Cu-doped ZnO nanoparticles enhanced antibacterial potential of the composite sponge. Meanwhile, all sponge groups are safe for viability, proliferation and adhesion of human dermal fibroblast cells. Overall, the obtained data has proved the potential of carboxymethyl cellulose/gelatin/Cu-doped ZnO dressing as a promising candidate for managing infected wounds.