Antimicrobial activity and FTIR spectral properties of some phosphate glasses and glass-ceramics from the system P2O5-NaF-CaF2 and effects of dopants

Ternary fluorophosphates glasses doped with one of oxides: CeO2, ZnO, Ag2O, La2O3 were prepared by the melt-annealing technique. Differential thermal analysis of the prepared samples was conducted to obtain the suitable temperatures for thermal heat treatment of the parent glasses to be able to convert them to their corresponding glass-ceramics. X-ray diffraction analysis was carried out to identify the formed crystalline phases within the glass-ceramics. FTIR spectral studies of the prepared glasses and glass-ceramic was done to find out the structural building groups in the studied samples; indicated that the vibrational bands due to phosphate groups are mainly Q(2) and Q(3). That is because of the high content of P2O5 (70%), besides the sharing of vibration due to (PO3F) groups. FTIR of the glass-ceramics show sharp peaks correlated with the crystallinity with well-defined crystalline species and the changes of the intensities of the mid region absorption can be related to depolymerization effects. Antimicrobial activity of the doped glassy or glass-ceramic samples was assessed to justify their suitability as antimicrobial agents. Glassy samples revealed excellent antibacterial and antifungal effects as compared with glass-ceramics, and addition of Ag2O showed the best broad spectrum antimicrobial activity even at low concentration (0.1%). CeO2, La2O3 and ZnO exhibited good antibacterial activity and moderate antifungal effects when added to glassy samples.