CREPEC, Department of Chemical Engineering, Ecole Polytechnique de Montreal, PO Box 6079, Station Centre-Ville, Montreal, Quebec, Canada H3C 3A7.
Biomacromolecules. 2012 Feb 13;13(2):412-21. doi: 10.1021/bm201444v. Epub 2012 Jan 25.
Core-shell structured PEO-chitosan nanofibers have been produced using a coaxial electrospinning setup. PEO and chitosan solutions, both in an aqueous acetic acid solvent, were used as the inner (core) and outer (shell) layer, respectively. Uniform-sized defect-free nanofibers of 150-190 nm diameter were produced. In addition, hollow nanofibers could be obtained subsequent to PEO washing of the membranes. The core-shell nanostructure and existence of chitosan on the shell layer were confirmed by TEM images obtained before and after washing the PEO content with water. The presence of chitosan on the surface of the composite nanofibers was further supported by XPS studies. The chitosan and PEO compositions in the nanofibrous mats were determined by TGA analysis, which were similar to their ratio in the feed solutions. The local compositional homogeneity of the membranes and the efficiency of the washing step to remove PEO were also verified by FTIR. In addition, DSC and XRD were used to characterize the crystalline structure and morphology of the co-electrospun nonwoven mats. The prepared coaxial nanofibers (hollow and solid) have several potential applications due to the presence of chitosan on their outer surfaces.
采用同轴静电纺丝装置制备了核壳结构的 PEO-壳聚糖纳米纤维。PEO 和壳聚糖溶液分别以水溶液和乙酸溶液为内（核）层和外（壳）层。制备得到了直径为 150-190nm 的均匀、无缺陷的纳米纤维。此外，通过对膜进行 PEO 洗涤，可以得到中空纳米纤维。通过对洗涤前后的 TEM 图像进行分析，证实了纳米纤维具有核壳结构，壳层上存在壳聚糖。通过 XPS 研究进一步证实了壳聚糖存在于复合纳米纤维的表面。通过 TGA 分析确定了纳米纤维垫中的壳聚糖和 PEO 组成，其与进料溶液中的比例相似。通过 FTIR 还验证了膜的局部组成均匀性以及 PEO 洗涤步骤的效率。此外，还使用 DSC 和 XRD 来表征共电纺无纺毡的结晶结构和形态。由于其外表面存在壳聚糖，因此制备的同轴纳米纤维（中空和实心）具有多种潜在应用。
