聚乳酸-聚己内酯复合纳米纤维支架的制备和表征

Fabrication and Characterization of Poly(L-lactic acid)-polycaprolactone Composite Nanofiber Scaffolds

在二氧六环/乙醇溶剂体系中,采用凝胶抽提相分离法制备了聚乳酸-聚己内酯(PLLA-PCL)复合纳米纤维支架,研究了凝胶温度、聚合物比例、聚合物浓度、致孔剂及二氧六环/乙醇(溶剂/非溶剂)比例对复合纳米纤维支架结构与性能的影响.结果表明,当凝胶温度处于-20^-10℃,PCL含量为30%~50%,非溶剂含量不超过15%,致孔剂与溶质质量比不超过20∶1时,均能得到具有类似于天然细胞外基质的纳米纤维(50~500 nm)结构的PLLA-PCL复合纤维支架.随着PCL含量的增加,复合纤维支架的弹性模量减小;PCL含量为30%时,复合支架的相容性和结晶性最好.该复合纤维支架具有良好的生物活性和一定的降解性能.

The feasibility of fabrication of poly （L-lactic acid）-polycaprolactone （PLLA-PCL） composite nano- fiber scaffolds using the gel extraction phase separation in the dioxane/ethanol solvent system was verified and the effects of gelation temperature, the ratio of PLLA and PCL, polymer concentration, the ratio of dioxane and ethanal and porogen on the structure and performance of PLLA-PCL composite nanofiber scaffolds were investigated. The results show that PLLA-PCL composite nanofiber scaffolds with 50--500 nm nanofiber structure similar to the extracellular matrixc（ECM） can be fabricated when the gelation temperature is in the range of -20-10 ℃, PCL content of 30% to 50%, the content of non-solvent no more than 15%, the porogen proportion no more than 1 ： 1. The additional PCL play a role of toughening, and the elastic modulus of the composite fiber scaffolds decrease with the increasing of PCL mass fraction. When the content of PCL is 30%, the compatibility and crystallinity of the composite fiber scaffolds are the best, and the composite fiber scaf- folds have a good bioactivity and certain biodegradability.