Elaboration and Characterization of Coaxial Electrospun Poly(ε-Caprolactone)/Gelatin Nanofibers for Biomedical Applications

Coaxial poly(epsilon-caprolactone) (PCL)/gelatin nanofibers were successfully fabricated by electrospinning, using 2,2,2-trifluoroethanol (TFE) as a solvent. The morphology of the PCL/gelatin coaxial fibers was evaluated using attenuated total reflectance Fourier transform infrared (FTIR) spectroscope, scanning electron microscope, and transmission electron microscope. The disappearance of gelatin absorption bands in FTIR spectrum after the mat washing step suggested that coaxial nanofibers were obtained. The coaxial morphology was confirmed by transmission electron microscopy. The influences of PCL concentration, applied voltage, and feed rate on the characteristics of the PCL core were analyzed in correlation with the structure of the nanofibers. The morphology of the coaxial fibers was observed to be mainly affected by the PCL solution concentration. Extraction of the PCL core using dichloromethane allowed the preparation of hollow gelatin nanofibers. The replacement of TFE by a formic acid-acetic acid (1:1) system as a less toxic solvent also successfully resulted in the preparation of coaxial PCL-gelatin nanofibers.