A self-healing hydrogel based on modified chitosan and sodium alginate oxide reinforced with hydrophilic nanomaterials for wound dressing applications.

N-carboxyethyl chitosan (CECS) and sodium alginate oxide (SAO) are two biomaterials extensively used in tissue engineering, particularly in wound dressing (WD) applications. Nonetheless, these materials exhibit certain limitations such as inadequate physicomechanical properties, limited antibacterial activity in non-acidic environments, and insolubilityunder physiological condition. This study introduces an injectable self-healing hydrogel composed of CECS and SAO, improved with hydrophilic nanomaterials, i.e., cellulose nanofibers (CNFs) and copper oxide (CuO) nanoparticles, to address the inherent drawbacks of these hydrogels. The CECS/SAO/CNFs/CuO hydrogels were analyzed by varying the CNFs concentration (0, 0.05, 0.10, and 0.15 wt.%) and CuO nanoparticles content (0, 0.008, 0.020, 0.032 wt.%). Physicomechanical properties (compressive modulus and strength, % degradation, swelling, and pore size), rheological characteristics, and biological performance (assessed by fibroblast cell growth, adhesion, and live-dead tests) of the hydrogels were evaluated. The findings indicated that the CECS/SAO hydrogel containing 0.10% CNFs and 0.032% CuO nanoparticles exhibited appropriate physical properties (2259% swelling after 1 h, 22.3% degradation after 6 days, and 151 µm pore size), compressive modulus (22.31 kPa), shear thinning behavior, and biological viability (more than 90% after 3 days), while ensuring adequate injectability and proper self-healing. The antibacterial property of the hydrogel against Staphylococcus aureus and Escherichia coli was observed to be higher than 99.5%. These results highlight the significant potential of the CCH/SAO/CNFs/CuO hydrogel for wound dressing applications.