重组人骨形态发生蛋白2对壳聚糖-明胶多孔复合支架理化性能的影响

Effect of Recombinant Human Bone Morphogenetic Protein-2 on Physicochemical Properties of Porous Chitosan-gelatin Scaffold

目的以组织工程学技术为基础,制备壳聚糖-明胶/骨形态发生蛋白2(BMP-2)多孔复合支架,讨论壳聚糖与明胶的不同配比及向复合材料中加入BMP-2对支架的微观结构和理化性能的影响。方法分别用不同配比的壳聚糖和明胶制备复合支架,并向1组配比中加入BMP-2。以扫描电镜观察支架的表面特征,测定支架的孔径值、材料的吸水率及表观密度。结果壳聚糖-明胶多孔复合支架比表面积大,内孔结构多形性高、且大量连通;壳聚糖与明胶配比为4︰1时的复合支架孔径最小,孔壁最厚;配比为1︰4时孔径最大,孔壁最薄;壳聚糖与明胶配比为1︰1时吸水率及表观密度达到最大,分别为(318±75)%和(0.085±0.013)g/cm3;向复合支架中加入BMP-2对支架的微观结构、吸水率及表观密度无明显影响。结论应用冷冻干燥法可以成功制备壳聚糖-明胶多孔复合支架,支架的微观结构与理化性能与壳聚糖与明胶的配比密切相关,向支架中加入BMP-2对材料的理化性能无明显影响。

Objective To investigate the physicochemical properties of porous chitosan-gelatin scaffold prepared with different proportions of chitosan and gelatin and incorporated with bone morphogenetic protein-2（BMP-2）.Methods Chitosan-gelatin scaffolds were prepared with different proporations of chitosan and gelatin,and the volume ratios of these two materials were 4∶1,1∶1,and 1∶4,respectively.BMP-2 was added into the scaffold with the volume ratio of chitosan to gelatin of 4∶1.The microstructure and porosity were observed under scanning electron microscope,and the pore diameter,rate of water absorption,and surface density were determined.Results For chitosan-gelatin scaf-fold,the specific surface area was large,and the endoporus was highly polymorphic and with many interconnections among them.The chitosan-gelatin scaffold with the volume ratio of 4∶1 had minimum pore diameter and maximum thickness,and the scaffold with the volume ratio of 1∶4 had maximum pore diameter and minimum thickness.The rate of water absorption and surface density reached the maximum val-ues（318%±75 % and 0.085±0.013 g/cm3）when the volume ratio was 1∶4.No obvious changes in the microstructure,rate of water absorp-tion,and surface density were found after BMP-2 was added.Conclusion We can prepare the porous chitosan-gelatin scaffold with freeze drying method.The physicochemical properties of the scaffold are correlated with the volume ratio of chitosan to gelatin,but not affected by BMP-2.