Molecular action and bioactivity characterization of electrospunchitosan-polylactic acid composite nerve conduit

The chitosan (CS)-polylactic acid (PLA) spinning solution was prepared using a composite solution of trifluoroacetic acid (TFA) and dichloromethane (DCM) as the solvent, and CS and PLA as the solute. Electrospinning and template coiling were used to prepare CS-PLA composite nerve conduit, and the comprehensive properties of CS-PLA composites were investigated. By characterizing the structure and properties of composites, the molecular interactions in CS and PLA systems were analyzed. Furthermore, through the co-cultivation experiments of composite nerve conduit and Schwann cells, the best system components for Schwann cells to grow and adhere to the inner wall of the catheter were proposed and verified. The results show that CS and PLA molecules are bonded by hydrogen bonds in the composite material, and the various hydrogen bond contributions are in the order of OH...OH>OH...N>OH...ether O. With the increase of PLA content, the thermal performance and thermal stability of the composites are increased, the tensile strength is increased by 197.7%, and the breaking elongation is increased by 53.7%. With the increase of CS content, the hydrophilicity and cell compatibility of the composites gradually increase. When the component ratio of CS∶PLA is 3∶1, the size of the grooves and micropores is the most favorable for Schwann cell adhesion.