Biovidros ativos multifuncionais dopados com prata e európio para aplicações biomédicas: caracterização, atividade antibacteriana, citocompatibilidade e potencial regenerativo

Abstract

Nanostructured bioactive glasses have emerged as promising biomaterials for bone repair, particularly when functionalized with ions capable of providing antimicrobial properties. This study aimed to evaluate the biological performance of bioactive glasses doped with silver and europium through physicochemical characterization, in vitro assays, and in vivo evaluation in an experimental model. Structural characterization confirmed the formation of a typical SiO₂– Na₂O–CaO–P₂O₅ glass network, with structural modifications associated with silver incorporation. In vitro results demonstrated that silver-containing formulations exhibited concentration-dependent antibacterial and antibiofilm activity against Staphylococcus aureus, Escherichia coli, and Streptococcus mutans, while maintaining high cytocompatibility in Vero cells. Europium incorporation did not significantly influence the evaluated biological parameters. Based on these findings, formulations containing 0.5 wt% and 1.25 wt% silver were selected for in vivo evaluation in a rat calvarial defect model. The results showed that silver concentration directly modulated tissue response, with 0.5 wt% promoting a more pronounced initial inflammatory response, whereas 1.25 wt% was associated with increased collagen deposition and extracellular matrix maturation. In conclusion, silver doping confers multifunctional properties to bioactive glasses, highlighting their potential for bone tissue engineering applications. The dopant concentration plays a critical role in balancing antimicrobial efficacy and biological response.