TiO 2 Nanocomposite GelMA Film as Wound Dressing: Physicochemical, Structural, Mechanical and Antibacterial Properties

Bacterial infections can delay the wound healing and represent serious medical problems both in the hospital and community setting. In this work a gelatin hydrogel modified with photo-cross-linkable methacrylamide groups at 10% concentration (GelMA10%), enriched with titanium dioxide nanoparticles (TiO2NPs) and loaded with Neomycin Sulphate was developed with the aim to realize a tissue for wound care with improved mechanical and antimicrobial properties. TiO2 nanocomposite GelMA films with two TiO2NP concentrations were characterized to assess physicochemical, structural and mechanical properties by Scanning Electron Microscopy equipped with energy-dispersive X-ray spectrometer (SEM/EDX), micro-Computed Tomography (micro-CT) and X-ray Photoelectron Spectroscopy (XPS). Nanocomposite GelMA films showed more compact structure, reduced pore sizes and higher compressive modulus at the increasing NP concentration. They were able to absorb and retain water for prolonged time, however no significant differences in the swelling degree at the increasing of NP concentration were observed. In vitro drug release and antibacterial activity against Staphylococcus aureus of nanocomposite GelMA film enriched with 1 mg/ml of TiO2NPs, identified as good candidate for wound healing, were investigated. Both GelMA and TiO2 nanocomposite GelMA films loaded with drug exhibited a strong antibacterial action, whereas GelMA containing only TiO2NPs did not show any antimicrobial properties.