Bioactive glass: an in-vitro comparative study of doping with nanoscale copper and silver particles

Abstract

Bioactive glasses (BGs) based on 50SiO2-45CaO-5P2O5 system doped with 1, 5, and 10 mol% CuO or Ag2O were separately synthesized using quick alkali sol-gel method. Scanning electron microscope (SEM) analysis of the samples confirmed the formation of nano-sized BGs, whereas Fourier transform infrared (FTIR) spectra showed characteristic peaks for silica and phosphate groups. X-ray diffraction (XRD) pattern of the heat-treated (700°C) samples revealed the presence of crystalline metallic silver phase in all Ag-doped samples, while the XRD pattern of Cu-doped and control sample (50Si-45CaO-5P2O5) also heat-treated at 700°C confirmed their amorphous nature. Ultraviolet-visible (UV-Vis) studies along with Energy-dispersive X-ray spectroscopy (EDX) analysis confirmed the successful incorporation of Cu and Ag in bioglass. Antibacterial properties of the synthesized BGs were investigated by quantitative viable count method, and the results were related to the ion release profiles of the samples studied by flame atomic absorption spectroscopy (FAAS). Fast initial release of Ag observed in this study makes Ag-doped BG a better rapid bacteria-killing agent than Cu-doped BG, which exhibited a prolonged release of ions, suggesting that it may be a better candidate for long-term antibacterial protection.