Electrospun chitosan-graft-poly (ɛ-caprolactone)/poly (ɛ-caprolactone) cationic nanofibrous mats as potential scaffolds for skin tissue engineering

This research is aimed to develop cationic nanofibrous mats with improved cellular adhesion profiles and stability of three-dimensional fibrous structure as potential scaffolds for skin tissue engineering. Firstly, amino-remained chitosan- graft-poly (e{open}-caprolactone) (CS- g-PCL) was synthesized with a facile one-step manner by grafting e{open}-caprolactone oligomers onto the hydroxyl groups of CS via ring-opening polymerization by using methanesulfonic acid as solvent and catalyst. And then, CS- g-PCL/PCL nanofibrous mats were obtained by electrospinning of CS- g-PCL/PCL mixed solution. Scanning electron microscopy (SEM) images showed that the morphologies and diameters of the nanofibers were mainly affected by the weight ratio of CS- g-PCL to PCL. The enrichment of amino groups on the nanofiber surface was confirmed by X-ray photoelectron spectroscopy (XPS). With the increase of CS- g-PCL in CS- g-PCL/PCL nanofiber, the content of amino groups on the nanofiber surface increased, which resulted in the increase of zeta-potential of nanofibers. Studies on cell-scaffold interaction were carried out by culturing mouse fibroblast cells (L929) on CS- g-PCL/PCL nanofibrous mats with various contents of CS-g-PCL by assessing the growth, proliferation and morphologies of cells. The results of MTS assay and SEM observation showed that CS- g-PCL/PCL (2/8) mats with a moderate surface zeta-potential (ζ= 3 mV) were the best in promoting the cell attachment and proliferation. Toluidine blue staining further confirmed that L929 cells grew well and exhibited a normal morphology on the CS- g-PCL/PCL (2/8) mats. These results suggested the potential utilization of CS- g-PCL/PCL (2/8) nanofibrous mats for skin tissue engineering.