Preparation and characterization of electrospun human hair keratin / poly (ethylene oxide) composite nanofibers

Keratin, as one of the most abundant proteins, has been widely used for bio-related applications due to its biocompatibility and biodegradability. In this study, keratin was extracted from human hair by sulphitolysis extraction method and then blended with poly (ethylene oxide) (PEO) at different proportions. The keratin/PEO mixture was dissolved in distilled water, and finally electrospun into composite nanofibers. The viscosity of keratin/PEO solution reduced with the increase of keratin mixture ratio. The viscosities of the solutions at mixture ratios of 30/70 and 40/60 keratin/PEO showed flow curves comparable with that of 6 and 4wt% pure PEO solutions, respectively. The morphology, structure, and thermal property of the composite nanofibers were evaluated by Scanning Electron Microscope (SEM), Fourier Transform infrared spectroscopy (FTIR), and Differential Scanning Calorimetry (DSC), respectively. SEM analysis revealed that the morphologies of nanofibers were determined by the keratin content of keratin/PEO blend. Bead-free nanofibers could be found when the mixture ratio of keratin was below 70 wt% in the blend. FTIR analysis indicated that electrospinning process induced structural modifications in both the crystalline microstructure of pure PEO and keratin chains with a planar conformation with respect to the helical conformation. Thermal behavior of the keratin/PEO composite nanofibers showed that a high draw occurred in the electrospinning process causing the protein chains a less complex super-molecular reorganization that denatured at lower temperatures. The keratin/PEO composite nanofibers has potential for biomaterials such as cell culture substrate.