Synthesis, structure, bioactivity and biocompatibility of melt-derived P2O5‐CaO‐B2O3‐K2O‐MoO3 glasses

Abstract New glasses following the P 2 O 5 ‐CaO‐B 2 O 3 ‐K 2 O‐MoO 3 composition were prepared using the classical melt quenching method in order to investigate and correlate their structural peculiarities with the composition and, moreover, with the bioactivity and biocompatibility behavior. The structure and surface morphology of samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Two complementary techniques were used to determine the elemental composition inside samples and on the outermost layer of their surface, namely energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS), respectively. For assessing in vitro the bioactivity of the synthesized glasses, the ability to form hydroxyapatite crystallites on their surface upon immersion in simulated body fluid (SBF) was checked using SEM and EDX analysis. The in vitro cytotoxic effect of samples was evaluated using a mitochondrial activity assay. The results reveal that the increase of MoO 3 content in the P 2 O 5 ‐CaO‐B 2 O‐K 2 O composition generates a continuously disordering of the local structure and the increase of Mo 6 + /Mo 5 + ratio values on samples surface. No bioactivity was observed for this glass system after 15 days of immersion in SBF. The in vitro toxicity studies show that samples containing MoO 3 up to 7mol% have a good biocompatibility with healthy human immortalized keratinocyte (HaCaT) cell line.