静电纺丝法制备胆固醇-g-聚乳酸液晶/聚乳酸复合纳米纤维膜

摘要

以辛酸亚锡为催化剂,胆固醇(CHOL)为共引发剂引发D,L-丙交酯开环聚合,制备了胆固醇-g-聚(D,L-乳酸)(CHOL-g-PDLLA)低聚物,采用偏光显微镜(POM)和差示扫描量热(DSC)方法考察了其液晶特性.通过静电纺丝技术制备了CHOL/PDLLA和CHOL-g-PDLLA/PDLLA复合纳米纤维膜,对其形貌、界面相容性、孔隙率、拉伸性能和细胞相容性进行了研究.结果表明,CHOL-g-PDLLA为一种热致胆甾型液晶,液晶温度区间为21.8～74.5℃；CHOL-g-PDLLA/PDLLA复合纳米纤维膜的纤维形态良好,表面均匀光滑,孔隙率在70％ ～ 75％之间,且其界面相容性优于相应的CHOL/PDLLA.随着CHOL和CHOL-g-PDLLA含量的增加,复合纳米纤维膜的拉伸强度逐渐下降,但CHOL-g-PDLLA/PDLLA复合纳米纤维膜的拉伸强度显著大于CHOL/PDLLA.体外骨髓间充质干细胞培养结果显示,CHOL-g-PDLLA/PDLLA复合纳米纤维膜具有良好的细胞相容性,且优于相应的PDLLA和CHOL/PDLLA纳米纤维膜.%Cholesterol-graft-poly (D,L-lactic acid) (CHOL-g-PDLLA ) oligomer was synthesized by the ring-opening polymerization of D, L-lactide using stannous 2-ethylhexanoate as catalyst and cholesterol (CHOL) as co-initiator, and the liquid crystalline properties was observed by polarizing microscope and differential scanning calorimetry. Then, CHOL/PDLLA and CHOL-g-PDLLA/PDLLA composite nanofiber membranes were prepared by electrospinning. The micrograph, interfacial compatibility, porosity, tensile properties and cellular compatibility of the composite nanofiber membranes were studied. The results show that CHOL-g-PDLLA is a thermotropic cholesteric liquid crystal with liquid crystal temperature range of 21.8-74.5℃. CHOL-g-PDLLA/PDLLA composite nanofiber membranes with good fiber micrograph, smooth surface and porosity of 70% to 75% were obtained, and the interfacial compatibility was significantly better than that of CHOL/ PDLLA. With the content of CHOL or CHOL-g-PDLLA increased, the tensile strength of CHOL/PDLLA and CHOL-g-PDLLA/PDLLA composite nanofiber membranes both decreased, but the tensile strength of the latter is always greater than that of the former. The results of mesenchymal stem cells culture in vitro indicate that the cellular compatibility of the CHOL-g-PDLLA/PDLLA composite nanofiber membranes is very good, and better than those of pure PDLLA and CHOL/PDLLA nanofiber membranes.