Fabrication and Cellular Compatibility Study of Polycaprolactone/Chitosan Nanofiber with Porcine Tracheobronchial Epithelial Cells.

摘要

Chitosan is a natural polymer known for its great biocompatibility, antibacterial properties, and cytocompatibility. These features make it a great candidate for scaffold material, preferably in the form of nanofibers. In some areas of tissue engineering, such as tracheobronchial regeneration, nanofiber scaffold material should be biodegradable, biocompatible, elicit limited cytotoxicity, and exhibit sufficient mechanical properties. The objective of this research is to develop nanofiber material from chitosan (CS) and polycaprolactone (PCL) that has cellular compatibility with porcine tracheobronchial epithelial cells, minimal cytotoxicity, and acceptable mechanical strength. The material will be used as a scaffold for regenerating trachea tissue after extensive injury. Nanofibers were produced using a laboratory built electrospinning device induced by gravity and the electrical field. At first, chitosan was depolymerized and then blended with polycaprolactone dissolved in trifluoroethanol. The absence of organic acid, unlike what is seen in several other chitosan electrospinning, was designed to eliminate degradation of PCL and possible complications with biocompatibility studies later one. Fiber morphology and chemical structure analysis was performed to confirm nanofiber structure and fiber composition. Mechanical strength tests of the nanofibers demonstrated the elasticity and ductility to be seen from the assortment of PCL/CS ratios. To assess biological potential, porcine tracheobronchial cells were seeded onto nanofiber substrates with different ratios of PCL/CS (i.e. 100/0, 90/10, 80/20, and 70/30) by using a unique insert design for a 7 day culture session. Lactase dehydrogenase assay was carried out at different time points to determine cytotoxicity levels as well as Western Blot analysis for protein levels of beta-Actin, Cox-2, Phos-IkappaB, and iNos. This study shows that chitosan based nanofibers blended with PCL had sufficient structural integrity and serves as a potential candidate in tracheobronchial tissue engineering at low chitosan levels.