Cytocompatibility studies of titania-doped calcium borosilicate bioactive glasses in-vitro

Abstract

The present study aims to elucidate the applications of Titania (TiO₂) doped calcium borosilicate glass as a biocompatible material in regenerative orthopedic applications. In this context, we have examined the bioactivity of various concentrations of TiO₂ doped glasses with the help of simulated body fluid (SBF). Cytocompatibility, cell proliferation, and protein expression studies revealed the potential candidature of TiO₂ doped glasses on osteoblast cell lines (MG-63). We hypothesized that TiO₂ doped calcium borosilicate glasses are most cytocompatible material for bone implants. Glasses with composition 31B₂O₃-20SiO₂-24.5Na₂O-(24.5-x) CaO- x TiO₂ (x=0,0.5,1,2) have been prepared by the conventional melt-quenching technique. After immersion of glasses in the SBF, formation of hydroxyapatite layer on the surface was confirmed by X-ray Diffractometer (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) analysis. Significant change in the pH of the body fluid was observed with the addition of titania. Degradation test was performed as per the ISO 10993. The results showed that partial substitution of TiO₂ with CaO negatively influenced bioactivity; it decreased with increase in concentration of TiO₂. Vickers hardness tester was used to measure the microhardness values of the prepared glasses. With the increasing of TiO₂ content, the microhardness of the glass samples was increased from 545Hv to 576Hv. Cytocompatibility has been evaluated with MG-63 cells by using MTT assay. Further, we observed that there was no change in expressions of cyclin levels even after the incorporation of titania. The antibacterial properties were examined against E. coli and S. aureus. Strong antibacterial efficacy was observed for 2% TiO₂ in the system. Hence it can be concluded that titania-doped borosilicate glasses may be used as potential materials in bone tissue engineering.

Keywords: Bioactivity; Biocompatible material; Cell viability; Cytocompatibility; Human osteoblast cells; Proliferation.