Fabrication Of Sr-containing Bioglass/HA Composite And Its Solubility

Abstract:Bioglass and hydroxyapatite both become a hotspot in the research of the biological materials because of their biocompatibility and biological activity, but bioglass has a quick dissolution rate, which would reduce the long-term stability of the implant, and hydroxyapatite has a low dissolution rate. At the same time, it was reported that the human body bone contains a small amount of strontium, magnesium and other elements, and strontium element can promote osteoblast proliferation and treatment of osteoporosis.In our study, CaO-P2O5-SiO2-SrO based bioactive glasses containing different amount of Sr were prepared via colloidal-sol gel method. Then the best content bioglass will composite with hydroxyapatite. Surface characterization were evaluated by X-ray powder diffraction (XRD) and scanning electron microscope (SEM). Solubility and in vitro bioactivity of bioglasses with different Sr content were investigated by soaking them in Tris solution and simulated body fluid. The MC3T3-E1osteoblast cell culture studies the cell activity of the bioglass. The results show that:(1) Strontium partly replacing calcium can control the dissolved rate of the bioglass, the addition of strontium can inhibit the dissolution of bioglass, and its dissolution rate reduced with strontium content increasing.(2) Strontium containing bioglass has nice biological activity in simulated body fluid, strontium element has participate in the biomineralization of bioglass, and with the increase of content of strontium element, the crystalline of hydroxyapatite is abate, but actually human bone is weak crystalline, so it may strengthen its biological activity.(3) In cell compatibility experiments of Strontium containing bioglass,5wt%SrO content biological glass is the best not only density of cell surface adsorption, but also cell pseudopodia. Cells can close adsorption on the surface material, shows that5wt%SrO content of bioglass has better biological activity and cell affinity. (4) Prepared of doped strontium bioglass/hydroxyapatite composite material, find that all composite material have very good biomineralization properties, the surface of composite materials is smoother, the dissolved rate of material is slower with the increase of hydroxyapatite content in composite materials, but the dissolution rate of composite materials is far quicker than the pure hydroxyapatite.(5) All composite materials soaking in the simulated body fluids exist a dissolution and deposition process, and with the increase of hydroxyapatite content deposition rate is slower, sediment is less, and poorer crystalline.