载rhBMP2凝胶微球控释系统的设计与合成实验

Development of a hydrogel microsphere delivery system for rhBMP2

目的:设计与合成rhBMP2新型控释载体,初步探讨其载药及降解性能.方法:用右旋糖酐(dextran,dex)与甲基丙烯酸缩水甘油酯(glycidyl methacrylate,GMA)合成甲基丙烯酸缩水甘油酯右旋糖酐(dex-GMA),测定该凝胶微球溶胀系数Q,并对其载药、降解性能进行初步研究.结果:dex-GMA在一定条件下可以成球,粒径与制备工艺密切相关;该凝胶微球溶胀参数10.9±5.3;载药性能良好,在葡聚糖酶的作用下20～40 d内可以完全降解. 结论:右旋糖酐基凝胶微球具有良好的溶胀性能,可生物降解,其粒径可控,作为生长因子载体,有望达到控释给药的目的,其制备工艺及理化性能有待进一步研究.

Objective: To design and synthesize a novel vector for rhBMP2 delivery system in tissue engineering. Methods:Dextran glycidol methacrylate(dex-GMA) was synthesized with dextran(dex) and glycidol methacrylate(GMA).Dex-GMA microspheres were prepared by suspension polymerization. The swelling behavior of the microspheres was evaluated by the swelling equilibrium parameter Q. The biodegradation properties of the dextran-based hydrogel microspheres were assessed by the surface morphology before and after biodegradation. Results:Microspheres of dex-GMA in the size(diameter) of 20 to 80 μm with good configuration were produced. Q value of the microspheres with the diameter of 20-30 μm was 10.9±3.3,that of those with 70-80 μm 8.9±6.4.Stirring speed, span-80(emulsifer) quantity and the proportion of dex-GMA affected the size of the microspheres. rhBMP2 was enveloped into the microspheres. Complete degradation of the microspheres was observed during 20 to 40 days at 37 ℃ in normal saline. Conclusion: Dex-GMA hydrogel microspheres may be a release controlling system for rhBMP2 delivery.