Gallium- and Cerium-Doped Phosphate Glasses with Antibacterial Properties for Medical Applications

Novel cerium- (Ce) and gallium (Ga)-doped phosphate glasses (PGs) are successfully obtained by the peroxidation method. The new glasses are characterized using Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction, inductively coupled plasma-optical emission spectroscopy (ICP-OES), and pH measurements. A strong correlation between glass properties and their composition is found. The incorporation of Ga/Ce in the glass structure is confirmed by peak shifts in Raman and FTIR spectra. Degradation tests conducted in water confirm the soluble character of the PGs and reveal the influence of Ga and Ce on the degradation rate. Ga-doped glasses are found to be less soluble than Ce-doped ones (43%, 33%, 21%, and 16% of dry mass remained after 7 weeks for 7Ga, 5Ga, 5Ce, and 7Ce, respectively). Biological evaluation using ST-2 cells shows adequate cell response with a cell viability of 80% measured using the indirect contact method depending on the composition. The cell viability decreases with an increase in Ga content and increases with Ce content. The antibacterial character of Ga/Ce-doped PGs is confirmed by turbidity measurements against Escherichia coli and Staphylococcus carnosus. The novel Ce/Ga-doped PGs exhibiting antibacterial properties and biocompatibility reported here are interesting for tissue engineering and wound healing applications.