Incorporation of B and V oxides into bioactive glass by melt quenching: In vitro studies for bone regeneration applications

In this study, glass-ceramics with a weight composition of 40-X% SiO₂, 24.5 % CaO, 14.5 % Na₂O, 6.0 % P₂O₅, 15 % B₂O₃, and X% V₂O₅ (X = 1, 3, and 5) were produced using the melt quenching method. Vanadium pentoxide and boron oxide were suggested to lower production melting temperatures. Several techniques were used to confirm the composition and amorphous nature of the glass-ceramics, including X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TG), energy dispersive spectroscopy (EDS), and differential thermal analysis (DTA). All samples were incubated in simulated body fluid (SBF) solution at 37 °C for 3, 7, 14, and 21 days to determine their bioactivity under in vitro conditions. The XRD pattern indicates insufficient crystalline phase formation, possibly due to V₂O₅ inhibiting apatite growth and promoting amorphous calcium phosphate. Precipitates in the glass-ceramic show increased lattice constants when apatite combines with boron. SEM images reveal surface precipitation and the development of hydroxyapatite (HA) after 21 days of immersion in SBF; EDS analysis confirms the presence of the expected ions. The Fourier Transform Infrared Spectrophotometer (FTIR) analysis shows the dominance of the silicate network in the glass-ceramics, with characteristic bands at specific frequencies.