Preparation and characterization of PDLLA/chondroitin sulfate /chitosan scaffold for peripheral nerve regeneration

A novel bioactive and bioresorbable PDLLA/chondroitin sulfate/chitosan scaffold was prepared via layer-by-layer(LBL) electrostatic-self-assembly (ESA) and the thermally induced phase separation (TIPS) technique. Chondroitin sulfate and chitosan were alternately deposited on the activated PDLLA substrate. The deposition process was monitored by UV-Vis absorbance spectroscopy. After frozen and lyophilized, the scaffold was characterized by attenuated total reflection (ATR)-FT-IR, XPS, SEM and AFM. The results showed that the scaffold was modified uniformly with a dense inner layer with few detectable pores and a porous sponge outer layer with the pore size about 5 μm, there was an obvious across section and the average thickness of each layer was about 9.4 nm.