Keratin Extracted from Chicken Feather Waste: Extraction, Preparation, and Structural Characterization of the Keratin and Keratin/Biopolymer Films and Electrospuns

Abstract

In this work, keratin was extracted from chicken feather waste via an environment-friendly method, sulphitolysis method, by using various sodium metabisulphite contents (0.0–0.5 M). Percentage yield and molecular weight of the extracted keratin were characterized by gravimetry and gel electrophoresis (SDS-PAGE), respectively. It was found that the yield increased, with the increase of sodium meta-bisulphite content, to the maximum value of 87.6 % yield, by using sodium meta-bisulphite content at 0.2 M. Molecular weight range of the product also decreased with the increase of the sodium meta-bisulphite content. The extracted keratin, with highest molecular weight ranged between 12 and 20 kDa, was further used for fabricating into fibers by using the electrospinning process. It was found that pure keratin solution could not be electrospun into fiber. However, by blending keratin with more than 10 wt% PLA, the fibers can be prepared. Results from FTIR and DSC also reveal that the crystal structure of the keratin changed from the β-sheet structure (rigid and small displacement characteristic) to the α-helix structure (elastic and large displacement characteristic) after keratin/PLA blends (10–50 wt% keratin) were prepared by the electrospinning method.