Processing keratin from camel hair and cashmere with ionic liquids

Keratin, a fibrous protein, that is available from a variety of animal sources as a constituent of hair, nails, horns, hoofs, wool and feathers, has applications in pharmaceutics, cosmetics and as a fertilizer. Like many naturally-derived biomaterials, the intrinsic biological activity and biocompatibility of keratin render this polymer a potential candidate for applications in medicine, and for the fabrication of scaffolds for tissue engineering. While several sources of keratin can be considered, the bioactivity of the keratins obtained can be quite different. In this study we discuss the processing and characterization of keratin from camel hair and goat cashmere. Specifically, the camel hair and cashmere were dissolved in an ionic liquid (1-butyl-3-methylimidazolium chloride), and the characteristics of the soluble and insoluble keratin were evaluated. The structure and properties of the raw material, soluble, and insoluble keratin were studied. Compared to the starting material, the soluble keratin showed chemical changes viz. decrease of cysteine, and minor structural changes. Preliminary in vitro biological properties performed by a lactate dehydrogenase (LDH) assay and scratch test showed good bioactivity in keratin from both sources. In particular, cell migration was observed to be faster when cells were cultured in the presence of soluble keratin extracted from camel hair and cashmere.