Bioactive glasses (BGs) are one of the most promising bone regeneration materials because they can bond to bone and simulate new bone growth. Sol-gel methods for producing BG are well established, however challenges still remain in selecting and optimizing the precursors. Even for BGs with the same final composition, different precursors may lead to different structures and properties of the gel derived BG. In this work, three different phosphorus precursors, phytic acid (PA), triethyl phosphate (TEP) and n-butyl phosphate (BP) were used to prepareBG (54.2%SiO2-35%CaO-10.8%P2O5, mol%). The obtained materials were characterized by TGA, FTIR, XRD, HEXRD, solid state 31P, 29Si NMRand by in vitro tests in SBF. It was found that the materials prepared by TEP or BP showed small amounts of crystallization, whereas the resulting material prepared by PA remained amorphous and had more P atoms as orthophosphate. In vitro assays indicated that all these materials were bioactive, while the BG prepared by PA showed the highest in vitro bioactivity, followed by TEP and, finally, BP. Based on these observations, it appears that phosphorus precursors have a significant impact on both the structure and bioactivity of the sol-gel derived BG. Results suggest that PA should be used in preference to TEP or n-butyl phosphate for the synthesis of sol gels. PA may improve the homogeneity of the sol gel glasses, reduce crystallization and lower stabilization temperatures.
Bibliographical note© 2017 IOP Publishing Ltd
Funding: National Natural Science Foundation of China (Grant No.: 81470101 and 51473004), the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No. XDB12020300) and a Royal Society/Natural Science Foundation ofChina international exchange grant (IE131323, 513111170)
- Bioactive glass
- Phosphorus precursors
- Sol gel