Doping of Strontium into Natural Bone Powder and Further Cell Experiment

Superior bone repairing materials can shorten bone healing periods and lower the incidence of nonunion. Strontium ions are known for enhancing a bone forming effect. Doping of strontium into bone powder will be able to make an attractive bone repairing material. In this study an ion exchange method was tried to dope strontium into bone powder in vitro. The capability to dope strontium into bone tissue was also observed. The cytotoxicity of novel material was investigated by MTT (Methyl thiazolyl tetrazolium assay) method. And further primarily cultured osteoblast was used to evaluate the biocompatibility of novel strontium doped bone sample. It is found that more than 10% exchange ratio of Sr/Ca can be achieved in bone powder. The Sr-doped bone shows no cytotoxicity. Compared with untreated bone samples, osteoblasts show higher proliferation rate (129%) on Sr-doped bone samples. And ALP (Alkaline phosphatase) is 132% higher on Sr-doped bone samples. Thus it is feasible to develop a Sr-doped allograft bone graft by this method.