BMP/α-TCP骨水泥蛋白释放试验

A Novel Self-Setting Bone Cement of BMP/α-TCP:Protein Release Experiment

目的 :观察BMP/α -TCP中BMP释放规律及其对材料固化时间和强度的影响。方法 :α -TCP与BMP及调合液混合制成直径 4mm、长 8mm圆柱体 ,按BMP含量不同 (1%、 2 % )制备A、B两种复合材料 ,两种样品分别在水浴振荡器内 (37± 1℃ )持续振荡。测定溶液中蛋白质含量、样品固化 2 4小时及BMP释放 4周后强度及蛋白释出试验前后样品的X线衍射图。结果 :3天之内样品A、B的BMP释放率分别达 2 4 6 3%及 37 6 7% ,10天时释放率分别达 31 4 %及 4 3 13%。BMP不影响材料固化时间 ,BMP释放后材料强度随浸泡时间延长而增高 ,X线衍射分析表明材料向HA转化。结论 ;BMP以扩散方式释放 ,3天内有一爆发性释放 ,10天内一直保持较高的释放速度 ,持续至 4周时仍有缓慢释放 ;BMP不影响材料的最终强度及其向HA转化。

Objective:To investigate the rules of BMP-delivering from BMP/α-TCP,affecting of BMPon the setting-time of bone cement and the changing of the strength of the material before and after BMP released.Method:The mixture of α-TCP solid phas and lyophilized BMP dust were mixed with fluid phas of the bone cement according to a solid-fluid ratio of 1∶0.4(W/V).The paste was molded as cylinders of 8mm long with diameter of 4mm and then was allowed to harden(setting process).With above method two kinds of BMP/α-TCP material were prepared:A contained 1%BMP and B contained 2%BMP.These two kinds of samples were put into 100ml glass eakers separately adding Ringers to 50ml.After sealed with double-deck polyet ylen plastic wafer,the beaker were put into water bath shake,then agitating lased to the end of the trail under a temperature of 37±1℃.The content of protein in solutions,the exponent strength and x-ray diffraction diagram were measured and determined during and after experiment.Result:Protein-releasing from BMP/α-TCP can be explained with Higuchi equation.At the beginning of the experiment,BMP released from BMP/α-TCP as a breaking out manner,the protein-releasing of sample A and B up to 24.63% and 37.6% respectively in 3 days.Protein-releasing rates were 31.4% and 43.13% from A and B respectively in 10 days.The setting time of the material did not affected by BMP,and its strength increased with the soaking time.The strength of BMP/α-TCP equals to pure α-TCP bone cement four days later and the x-ray diffraction diagram shows the truth of the material conversion to hydroxyapatite.Conclusion:BMP release from BMP/α-TCP bone cement in a diffuse manner,have a breaking out delivery in three dyas and keeping a high releasing rate in 10 days,then the release speed decreased markedly.But slow releasing still remained in the end of the experiment.The final strength of the material did not affected by BMP.