Stabilization of chitosan based electrospun nanofibers through a simple and safe method

A simple and safe method was used to stabilize nanofibrous structure of chitosan (CS) based mats obtained from acidic solution. The electrospun CS based nanofibrous mats were fabricated using CS/poly ethylene oxide in acetic acid aqueous solution. Exposure to water vapor at 40-70 degrees C for 30-120 min was implemented in order to stabilizing the CS mats. Scanning electron microscopy of the treated mats revealed preservation of nanofibrous structure after immersion in phosphate buffered saline (pH = 7.4). This result along with infrared spectroscopy and thermogravimetric analysis confirmed removal of acetic acid residues and neutralization of CS mats after treatment with water vapor. Stabilization with water vapor also led to augmentation in tensile strength and elastic moduli of CS mats comparing to as-spun mats while the elongation was decreased. Furthermore, the crystallinity and thermal stability of mats were slightly increased after neutralization. In comparison with glutaraldehyde cross-linked mats, water vapor treated mats showed higher swelling ratio and enhanced cell compatibility.