Chitosan-glycerol blended nanofibers for peripheral nerve regeneration applications

Over the last decade, chitosan has drawn increasing attention in the field of regenerative medicine as a natural polymer that is biocompatible, biodegradable, non-immunogenic and widely available. However, while chitosan scaffolds (e.g. nanofibers, films, etc.) have been developed by multiple methods, the application of these scaffolds has been hampered by the brittle and fragile nature of this material. Chitosan plasticization is possible as a means of improving mechanical properties, with the incorporation of glycerol within solid films having demonstrated its potential to enhance the mechanical properties of chitosan. In this work, we report the first use of plasticized chitosan for the production of nanofibers. We produced aligned glycerol plasticized chitosan nanofibers (Gly-Chi NFs) using electrospinning. Glycerol was used as a plasticizer in order to modulate the mechanical properties of chitosan. We optimized the production process and the glycerol concentration, and measured the surface wettability, FT-IR spectra and thermal properties of the NFs. We obtained continuous, defect-free Gly (2%)-Chi nanofibers with a diameter of 184 ± 6 nm and a high level of anisotropy. These Gly-Chi aligned nanofibers also exhibited biocompatibility with primary Schwann cells in vitro, and were effective in guiding their bipolarization, thus suggesting their potential for peripheral nerve regeneration applications.