Antibacterial and Biological Performance of Nanostructured Bioactive Glasses with Silver and Titanium Dioxide.

Abstract

Nanostructured bioactive glasses have attracted increasing attention as multifunctional biomaterials for infection-prone biomedical applications. In this study, pure and doped bioactive glasses incorporating silver (Ag₂O-derived species) and titanium dioxide (TiO₂) were evaluated for their antibacterial performance and in vitro cytocompatibility. Antibacterial activity was assessed against Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA). While the undoped bioactive glass showed no antibacterial effect, Ag- and TiO₂-doped formulations significantly reduced bacterial growth in a concentration-dependent manner. Ag-doped glasses exhibited the highest antibacterial efficacy, achieving complete inhibition of E. coli and MRSA at higher concentrations, whereas TiO₂-doped samples showed moderate inhibitory effects. Cytocompatibility was evaluated using an indirect assay with VERO CCL-81 cells, and all formulations maintained cell viability above 80%, including Ag-containing glasses at the highest tested concentrations. These results indicate that the incorporation of Ag and TiO₂ enhances antibacterial performance while preserving acceptable cytocompatibility under the tested conditions. Overall, these findings support the potential application of doped bioactive glasses in infection-prone bone repair scenarios; however, further studies on ion release, long-term stability, and in vivo biocompatibility are required.