Chitosan/TiO₂ composite membrane improves proliferation and survival of L929 fibroblast cells: Application in wound dressing and skin regeneration

The microbial infection and growth of fibroblasts are the critical factors for the effective wound healing. The natural polymer-based dressing membranes may mimic extracellular matrix to support the survival, proliferation and differentiation of fibroblasts. The present study deals with the preparation of chitosan/titanium dioxide (CS/TiO₂) composite membranes with different degree of TiO₂ incorporation, and their characterization in terms of morphology, ultrastructure, thermal behavior and mechanical properties with SEM, FTIR, XRD and tensile strength analyses. The data demonstrated the formation of strong O-Ti-O bonding between TiO₂ and CS resulting in superior porosity, mechanical strength, crystallinity and flexibility of the composite membranes. Further, the cyto-compatibility, proliferation, oxidative stress, cell cycle and apoptosis analyses of fibroblast L929 cells demonstrated the enhanced proliferation and survival, and decreased oxidative stress and apoptosis in L929 cells grown on CS/TiO₂ membrane incorporated with 025% TiO₂. Next, we measured the significant up-regulation in the expression of fibroblast-markers in L929 cells cultured on CS/TiO₂ (0.25%) membrane. Furthermore, the CS/TiO₂ composite membranes exhibited a superior antibacterial activity against Staphylococcus aureus. Taken together, the data confirmed that CS/TiO₂ (0.25%) membrane improved the growth, survival and functional integrity of fibroblasts, and exerted antibacterial activity which may be utilized as potential dressing materials.