| Objective To investigate the mineralization mechanism for the formation of a bone-like layered structure for borosilicate bioactive glass in vitro.Methods To simulate the internal environment, silicate glass (0B), borosilicate glass (2B) and borate glass (3B) were immersed in SBF solution or SBF solution containing gelatin for one week. The morphologies and phases of the mineralized products formed by the bioactive glass in SBF were systematically characterized and analyzed by mass loss analysis, SEM, EDS, XRD and FTIR. The glass structure of 2B and 3B glass was analyzed by solid state nuclear magnetic resonance.Results After soaking a week, the SEM results showed that the surfaces of borosilicate glass (2B) and silica-free borate glass (3B) were covered with a layered mineralisation coating, whereas the surface of silicate glass was not. XRD and FTIR results indicated that all of the three groups glasses contained the partial hydroxyapatite compounds of calcium phosphate. Solid-state nuclear magnetic testing resonance showed that a large number of [BO3] planar triangles were present in groups 2B and 3B. After immersion in the gelatin-containing SBF solution, the borosilicate glass (2B) still maintained the layered structure, and EDS analysis showed that the special layered structure was the mutually accumulated by the organic layers of gelatin and inorganic layers containing hydroxyapatite.Conclusion It was found that the two-dimensional met structure constructed by a lot of [BO3] plane triangles existed in 2B and 3B glasses. During the mineralization process, insoluble reactants were deposited on a two-dimensional plane structure, resulting in a layered structure of the mineralization products. The gelatin added to SBF can effectively adapt and combine with the layered mineralized structure of borosilicate glass, ultimately stacking a special intersected structure of organic and inorganic layers. |
