Forsterite Nanopowder: Structural Characterization and Biocompatibility Evaluation

Forsterite, a new biocompatible material was synthesized from Mg(NO3)2·6H2O and TEOS by using the sol–gel method. The material was then heated at 800, 900 and 1000 °C. The forsterite was noticed as the main crystalline phase in the material fired at 900 and 1000 °C, while periclase (MgO) was present in all the samples. The tests confirm that in the first two samples forsterite is present as crystallites <60 nm, while in the sample synthesized at 1000 °C it forms aggregates of micrometre-sized grains. In vitro test was performed by immersing the forsterite powder in the simulating body fluids (SBF) and hydroxyapatite formation on the surface was investigated. We could evidence the formation of hydroxyapatite on the forsterite surface after 7 days of immersion. The MTT test confirmed that forsterite powders dissolution promote osteoblast proliferation of the human-type osteoblasts with no significant cytotoxicity effects.