具有定向形貌的丝蛋白支架的制备

Preparation of Regenerated Silk Fibroin Directional Scaffolds

利用冰晶为模板并结合冷冻干燥技术,成功地获得了具有一定力学强度的定向多孔丝蛋白支架.采用扫描电镜、流变、拉曼光谱和压缩测试等方法,考察了丝蛋白原液在不同pH值和初始浓度的情况下对定向支架的成因、内部形貌及力学性能的影响.结果表明,当溶液的pH值为4.4,浓度由低到高时,所制备的丝蛋白支架内部将分别出现纤维状结构、轴向片层状和梭状多孔结构.特别是由初始浓度为15%(及以上)的丝蛋白溶液定向冷冻得到的支架,在压缩试验中表现出较好的力学性能,其轴向压缩模量和屈服应力分别达122.6和6.9MPa,满足了进一步应用的基本需求.

The directional freezing followed by freeze-drying techniques was used to successfully prepare regenerated silk fibroin （RSF） scaffolds with directional morphology and considerable mechanical properties. In order to investigate pH and concentration effect of the initial RSF solution on the morphology and mechanical properties of the scaffold, different methods, including the scanning electron microscopy, rheology, Raman spectroscopy, and mechanical test, were conducted. The results show that the morphology of the scaffold changes from fibrils to lamellar structures and then to cellular structures as the initial concentration of RSF solution at pH 4.4 increases. The RSF scaffolds with initial concentration of 15% or above show good mechanical properties, and the axial compression modulus is 122.6 MPa and the yield strength is 6.9 MPa. This would make the directional RSF scaffolds possible for further applications.