Bacterial infections can delay wound healing and represent serious medical problems both in the hospital and community settings, especially skin wound infections caused by Staphylococcus aureus. 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 concentrations of TiO₂NPs were characterized to assess physicochemical, structural and mechanical properties by scanning electron microscopy equipped with an energy-dispersive X-ray spectrometer (SEM/EDX), micro-computed tomography (micro-CT) and X-ray photoelectron spectroscopy (XPS). TiO₂ nanocomposite GelMA films showed a more compact structure, reduced pore sizes and a higher compressive modulus at the increasing concentration of TiO₂NPs. They were able to absorb and retain water for a prolonged time; however, no significant differences in the swelling degree at the increasing concentration of TiO₂NPs were observed. In vitro drug release and antibacterial activity against Staphylococcus aureus of TiO₂ nanocomposite GelMA film enriched with higher concentrations of TiO₂NPs, identified as a suitable candidate for wound healing, were investigated. Both GelMA10% and TiO₂ nanocomposite GelMA films loaded with drug exhibited a strong antibacterial action, whereas GelMA10% containing only TiO₂NPs did not show any antimicrobial properties.

In this study a dual delivery system, based on nanocomposite gelatin hydrogel, modified with photocrosslinkable methacrylamide groups and enriched with Halloysite nanotubes (GelMA-HNT) was developed to obtain a controlled and efficient delivery of Neomycin sulphate and Carvacrol in the management of skin infections caused by Staphylococcus aureus, dispersing antibiotic directly in GelMA-HNT matrix and entrapping Carvacrol into HNTs. The addition of 10% HNTs into GelMA led to a compact, honeycomb-like structure featuring smaller pores compared to the GelMA film, enhanced mechanical properties and good swelling capacity. 3.5 mg Carvacrol-loading into 10% HNTs led to a decrease in the compressive modulus, whereas no significant differences in swelling were observed. Optimized dual delivery nanocomposite film (Neom/Carv GelMA-HNT10%), containing 10 mg of Neomycin sulphate and 10% HNTs entrapping 3.5 mg of Carvacrol, exhibited different release profiles of active compounds, preferentially accumulated within synthetic membrane used as an artificial skin model and was able to kill bacteria starting 1 h incubation. The structural and mechanical properties, the ability to absorb and retain water, the release profiles, the local deposition of active compounds within the artificial membrane and the antibacterial activity seem indicate our film as a good candidate for the management of wound infections.

-Manufacturing of shape memory foams in hypergravity and simulated microgravity SANTO Loredana, IORIO Leandro, PROIETTI Alice, BELLISARIO Denise, QUADRINI F

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.