Preparation and characterization of PLLA/chitosan-graft-poly (ε-caprolactone) (CS-g-PCL) composite fibrous mats: The microstructure, performance and proliferation assessment.

In order to achieve the electrospinning of chitosan in common organic solvents, amino-reserved CS-g-PCL was synthesized by one-step method. PLLA and dichloromethane/ethanol (CH2Cl2/EtOH) solvent were chosen to prepare a series of different compositions of PLLA/CS-g-PCL mats (8/2, 6/4, 4/6, 2/8 wt/wt%) by electrospinning. The SEM showed that the smooth defect-free and uniform nanofibers were collected except PLLA/CS-g-PCL 2/8 and pure CS-g-PCL, and the fiber diameter was decreased from 828 nm to 461 nm with the increasing content of CS-g-PCL. The mechanical properties of composite mats have decreased with increasing CS-g-PCL content, but much higher than neat PLLA. The water contact angle, water absorption rate, water-vapor transmission rate and in vitro degradation behavior were 129°-19°, 109%-482%, 1945-2517 g m-2 day-1 and 4-14%, respectively. The addition of CS-g-PCL imparted PLLA/CS-g-PCL electrospun mats on better properties, improving the nature defects of PLLA. The in vitro cell culture studies showed that PLLA/CS-g-PCL 6/4 exhibited a higher in vitro biocompatibility and a better ability for cell attachment, spreading, and proliferation, comparing with PLLA mats. Herein, PLLA/CS-g-PCL 6/4 electrospun mats with excellent performance, was considered the potential application as wound dressing in skin tissue engineering.