Is Nano-Silver Safe within Bioactive Hydroxyapatite Composites?

Because of the abounded presence of the silver containing products in the market and intensively studied silver-containing biomaterials in the literature, we investigated a hypothesis that stabilizing silver within bioactive hydroxyapatite composite is capable to provide safe and effective antibacterial action. For that purpose nanocomposite made of bioactive, mineral hydroxyapatite (HAp) and antibacterial silver (Ag) is studied for interactions with both, bacterial and human cells. The nanocomposite provides controlled release of Ag ions; induces severe damages in bacterial cells and is capable for strong bacteriostatic and bactericidal action. On the other hand, investigations of the material's interactions with human cells confirm that lower concentrations are highly compatible with osteosarcoma and fetal lung fibroblasts, but at higher concentrations (that provide bacteriostatic and bactericidal influences in bacteria) the material is toxic and capable of inducing morphological changes similar to those observed in bacterial cells.