Preparation of hydrophilic poly(l-lactide) electrospun fibrous scaffolds modified with chitosan for enhanced cell biocompatibility

The methods of co-electrospinning and surface hydrolysis have been used for improving hydrophilicity of Poly(l-lactide) (PLLA), while most of them resulted in high shrinkage and changed mechanical properties of bulk polymers. In this study, we modify PLLA electrospun scaffolds by grafting chitosan by aminolysis technology. The results showed that the amount of grafted chitosan on fibrous scaffolds could be adjusted by controlling aminolysis time, and the hydrophilicity of scaffolds was dependent on the amount of grafted chitosan. Water contact angle of scaffolds were changed from 138.3° to 0°. Characteristic analysis of scaffolds indicated that aminolysis method did not affect the porous structure. The density of the modified scaffolds was between 0.48 and 0.54 g/cm3 and the tensile strength was between 3.24 and 3.45 MPa, which were statistically not different as compared to unmodified scaffolds (P > 0.05). The statistical analysis of the cell culture results showed that the cell proliferation on chitosan modified PLLA scaffolds were significantly improved as compared to that on the unmodified PLLA scaffolds (P < 0.05). All of results suggest that the aminolysis method is a convenient and effective mild chemical treatment method to improve hydrophilicity and cell biocompatibility of PLLA electrospun fibrous scaffolds for tissue engineering without sacrificing other properties.