The effect of borate on acellular bioactivity of novel mesoporous borosilicate bioactive glasses for tissue engineering

Abstract

Four novel mesoporous borate-based 13–93 bioactive glass has been synthesized by a modified Stöber method. Thermogravimetric analysis, Inductively coupled plasma atomic emission spectroscopy, Fourier Transform Infrared Spectroscopy, X-Ray diffraction, Brunauer–Emmet–Teller and Barrett–Joyner–Halenda, nuclear magnetic resonance and Scanning Electron Microscope attached with Energy-dispersive X-ray spectroscopy analyses were carried out to investigate the physicochemical properties, in-vitro acellular bioactivity, and the degradation rate of the bioactive glasses in simulated body fluid across a range of times up to 21 days. The characterization data indicates that the bioactive glasses are amorphous and possess mesoporous properties. Likewise, an increase in boron content reduced the surface area and pore volume of the bioactive glass series. The observed decline is attributed to borate units' smaller atomic radius than silicate. The ability to deposit a new apatite layer in the bioactive glasses depends on the borate concentration. As such, an increase in boron content resulted in a decrease in apatite formation. Additionally, the studies showed that bioactive glasses made of borate degraded more quickly than their silicate counterpart. Overall, borate-based 13–93 bioactive glasses were effectively synthesized, and the in-vitro results showed potential usage for these bioactive glasses in tissue engineering situations where it is desirable to control bone growth or delay the onset of bioactivity.