Design and development of an electrospun nanofiber using electrospinning technique for tissue engineering application

摘要

In order to overcome several limitations on currently available skin substitutes and wound dressings, the use of scaffolds made of synthetic biopolymer and natural bioactive polymer has been investigated. Chitosan (CS) is a natural “ green” biopolymer material which presents suitable properties to enhance wound healing and skin regeneration. Therefore, a biodegradable nanofibrous scaffold consisted of poly (e-caprolactone) (PCL) and CS was prepared via electrospinning technique for skin tissue engineering application. Several preliminary experiments were performed to examine the effects of varying polymer concentrations on the spin-ability of solution and the uniformity of nanofibers. The blend compositions contained 6, 8, 10, 12 and 14 wt.% PCL and 0.2, 0.4, 0.6, 0.8 and 1 wt.% CS in a mixed solvent system composed of 70 v/v% formic acid (FA) and 30 v/v% acetic acid (AA). The Wettability, water uptake and water vapor transmission (WVT) properties were determined to define the suitability of the scaffold to absorb excess exudates, provide thermal insulation, allow gaseous and fluid exchanges, and protect the wound against infection and dehydration. The optimum formulation of PCL/CS was obtained with 8 wt.% PCL and 0.8 wt.% chitosan. Further characterization studies were performed to evaluate the efficiency of these biodegradable nanofibers as a promising candidate for wound healing and skin tissue engineering. Bovine serum albumin (BSA) was used as a model protein to incorporate biochemical cues to the nanofibrous scaffolds. Tetracycline hydrochloride (TC) was incorporated in the electrospinning formulation to evaluate the drug release behavior and antibacterial properties. The tensile properties and degradation properties of PCL/CS nanofibers of different blend ratios were also determined. The nanofibers with higher amount of CS ratio showed enhancement in the hydrophilicity and have greater capacity in moisture transmission throughout the nanofibers in comparison with the pure PCL nanofibers. Average fiber diameters and pore sizes increased in the nanofibers containing BSA as a result of electrostatic interactions between the protein molecules and the functional groups of dissolved polymer. The in vitro cell culture results showed that the PCL/CS nanofibers were non-toxic to Human Dermal Fibroblast (HDF) cells. The HDF cells proliferated well in the PCL/CS blend nanofibers, significantly higher than the pure PCL nanofibers. Considering all the evaluation results, it can be concluded that the PCL/CS nanofibers have great potential to be used as a wound dressing material and skin tissue engineering scaffolds.