Cu-releasing bioactive glass coatings and their in vitro properties.

Bioactive glasses are well-known materials suitablefor bone-related applications thanks to their biocompatibility andosteoconductivity. In order to improve their in vivo performance,the modification of the glass composition by adding ions withspecific biological functions is required. As copper (Cu) possessesantibacterial properties, in this study, 5 wt % of CuO has beenadded to the 45S5 bioactive glass composition. The investigation ofthe effect of the Cu-containing bioactive glass on cellular behaviorhas revealed that the presence of Cu induces an early differentiationof human mesenchymal stem cells through osteoblast phenotype,promotes the expression of anti-inflammatory interleukin, andreduces proinflammatory interleukin expression. With the aim toproduce coatings with antibacterial properties, the Cu-containingbioactive glass was used as the target material for the pulsed laser deposition (PLD) of bioactive thin films. PLD experimentswere carried out at different substrate temperatures to study the effect on the film's characteristics. All of the films are compact,crack-free, and characterized by a rough morphology and good wettability. The in vitro bioactivity was demonstrated by theapatite growth on the coating surface, after soaking in simulated body fluid, revealed by Raman spectroscopy and scanningelectron microscopy?energy dispersive X-ray analyses. The antibacterial study proved that the material showed more effectiveactivity against three Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica) rather than againstGram-positive bacteria (Staphylococcus aureus).