【摘要】 背景:查阅文献发现在采用复乳溶剂挥发法制备缓释重组人骨形态发生蛋白2微胶囊的过程中,可以二氯甲烷、乙酸乙酯、丙酮或不同有机溶剂混合物等作为油相,而孰优孰劣尚无定论。目的:优化包封重组人骨形态发生蛋白2微胶囊制备方法,比较不同有机溶剂对微胶囊产生的影响。方法:分别以二氯甲烷(A组)、二氯甲烷与乙酸乙酯混合液(B组)、乙酸乙酯(C组)、乙酰丙酮(D组)等4种不同类型的有机溶剂作为油相,以聚乳酸-聚乙二醇-聚乳酸三嵌段共聚物为囊材,采用复乳溶剂挥发法制备缓释重组人骨形态发生蛋白2微胶囊,检测微囊的粒径、形态及包封率。将制备的微胶囊分别与第3代大鼠骨髓间充质干细胞共培养,培养14 d后检测碱性磷酸酶活性。结果与结论:A组微囊形态均一规则,微囊粒径小(4-10μm),包封率最高;B组、C组微囊粒径分布范围较大,包封率中等;D组微囊基本难成形,包封率最低。A组、B组、C组碱性磷酸酶活性明显高于D组(P<0.05),A组、B组均明显高于C组(P<0.05),A组与B组之间无明显差异。表明以二氯甲烷作为有机溶剂制备的重组人骨形态发生蛋白2微胶囊包封率高,形态优良且能很好地保护重组人骨形态发生蛋白2的生物活性。更多还原

【Abstract】 BACKGROUND:In literatures,the recombinant human bone morphogenetic protein-2(rh BMP-2) loaded microcapsules can be fabricated by double emulsion solvent evaporation method with different organic solvents,such as methylene chloride,ethyl acetate or their mixture. But so far it is not determined yet which one is better. OBJECTIVE:To optimize the preparation method of microcapsules encapsulating rh BMP-2 and to compare the effects of different organic solvents on the microcapsules.METHODS:Polylactic acid-polyethylene glycol-polylactic acid copolymer as microcapsules was used to prepare rh BMP-2 loaded microcapsules with double emulsion solvent evaporation method. Four kinds of organic solvents,methylene chloride(group A),mixture of methylene chloride and ethyl acetate(group B),ethyl acetate(group C) and acetyl acetone(group D) were chosen as oil phases to compare their effects on microcapsule’s morphology,diameter,and encapsulation efficiency. Passage 3 bone marrow mesenchymal stem cells from rats wereco-cultured with prepared microcapsules for 14 days,and then alkaline phosphatase activity was detected. RESULTS AND CONCLUSION:Compared with the other organic solvents,dichloromethane could cause microcapsules with the smaller and more uniform shape(4-10 microns) and the highest encapsulation efficiency; the microcapsules prepared by mixture of methylene chloride and ethyl acetate had relatively wide size distribution and moderate encapsulation efficiency; the microcapsules prepared by acetylacetone were difficult to form and keep the bioactivity of rh BMP-2. After cultured with rat bone marrow mesenchymal stem cells for 14 days,the alkaline phosphatase activity in groups A,B and C was significantly higher than that in group D and there was no significant difference between group A and group B; the alkaline phosphatase activity in groups A and B was significantly higher than that in group C(P < 0.05). The results show the rh BMP-2-loaded microcapsules prepared by methylene chloride as organic solvent have good shape,high encapsulation efficiency,and good biological activity.更多还原