骨形态发生蛋白复合支架的体外缓释性能

背景：临床试验证明纳米晶胶原基骨支架材料具有较好的组织相容性、合适的孔隙率及降解性能，但缺乏缓释生长因子的作用，且无成骨诱导性。 目的：将聚乙稀吡咯啉酮与骨形态发生蛋白复合后形成复合颗粒，再修饰纳米晶胶原基骨制备复合支架，观察骨形态发生蛋白的体外缓释效果。 方法：实验分3组，实验组取冻存管2支，每支放入5 mm×5 mm×5 mm 纳米晶胶原基骨1块，滴加聚乙稀吡咯啉酮混匀，-4 ℃冻存过夜，再滴加骨形态发生蛋白溶液，真空抽干后冻存；对照组1取冻存管2支，每支放入5 mm×5 mm×5 mm 纳米晶胶原基骨1块，滴加骨形态发生蛋白溶液，真空抽干后冻存；对照组2取冻存管2支，每支放入5 mm×5 mm×5 mm未脱钙的大鼠松质骨1块，滴加聚乙稀吡咯啉酮混匀，-4 ℃冻存过夜，再滴加骨形态发生蛋白溶液，真空抽干后冻存。观察14 d，采用ELISA法检测3组复合物骨形态发生蛋白的体外释放活性。 结果与结论：观察到14 d时，两对照组骨形态发生蛋白A值趋近于0，而实验组上清液中骨形态发生蛋白仍保持较高的A值，组间比较差异有显著性意义(P < 0.05)。表明经聚乙烯吡咯烷酮修饰后纳米晶胶原基骨支架具有明显缓释骨形态发生蛋白的作用。中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程全文链接：

Sustained-release capacity of bone morphogenetic protein composite scaffolds

BACKGROUND:Clinical trials have proved that nano-hydroxyapatite/collagen bone scaffold has good tissue compatibility, suitable porosity and degradation performance, but it is limited by the lack of sustained-release growth factors and induced osteogenic capacity. OBJECTIVE:To study the effect of the sustained-release system of polyethylene pyrrolinone modified nano-hydroxyapatite composite scaffold carrying bone morphogenetic protein. METHODS:Samples were divided into three groups, and there were two cryogenic vials in each group. In the experimental group, a piece of 5 mm×5 mm×5 mm nano-hydroxyapatite/collagen bone was placed per vial and mixed with polyethylene pyrrolinone at -4 ℃ overnight, and bone morphogenetic protein solution was then added followed by vacuum pumping and cryopreservation. In the control group 1, a piece of 5 mm×5 mm×5 mm nano-hydroxyapatite/collagen bone was placed per vial and mixed with bone morphogenetic protein solution followed by vacuum pumping and cryopreservation. In the control group 2, a piece of 5 mm×5 mm×5 mm non-decalcified rat cancellous bone was placed per vial and mixed with polyethylene pyrrolinone at -4 ℃ overnight, and bone morphogenetic protein solution was then added followed by vacuum pumping and cryopreservation. After 14 days, the in vitro release activity of bone morphogenetic protein in the three groups was detected using enzyme-linked immunosorbent assay. RESULTS AND CONCLUSION:After 14 days, the absorbance values of bone morphogenetic protein in the two control groups were close to 0, whereas the experimental group showed a higher absorbance value (P < 0.05). It indicates that polyethylene pyrrolinone modified bone morphogenetic protein/nano-hydroxyapatite composite  scaffold presents good sustained-release effects.