Dissolution of feather keratin in ionic liquids

Abstract

Keratin from various livestock industries is currently a waste material that has potential as a source of polyamide polymers that could replace fossil fuel derived materials if processing methods can be developed. In this work we have investigated methods for the dissolution and regeneration of keratin. Dissolution of keratin (from turkey feather) in ionic liquids was conducted under nitrogen at 130 °C for 10 hours. It was found that [BMIM]Cl, [AMIM]Cl and [choline][thioglycolate] could dissolve turkey feather keratin without addition of solvent or other chemicals. A significant percentage of solubility was obtained, up to 45% by weight. A water insoluble fraction was recovered by addition of water to the solution (∼50%). The structure and properties of this regenerated, water insoluble fraction were investigated. Compared to the starting material, the regenerated keratin shows structural changes rather than chemical changes within the polypeptide chains. The remaining fraction, consisting of water soluble fragments, was characterised by gel electrophoresis.

Steam Flash Explosion Assisted Dissolution of Keratin from Feathers

“…3 The ATR−FTIR spectra of the samples were shown in Figure 5 bending). 12 Figure 5A showed that no new functional groups appeared in the extracted keratin. Therefore, dissolution in the alkali solution did not strongly affect the peptide bonds of the feather keratin.…”

“…3 Feathers are readily available, low cost, renewable, and biodegradable, making them dependable biopolymer feedstock that should have similar properties to polyamides. 4,5 In recent years, researchers are looking for new applications of feather materials, such as food or compostable packaging, 2,6 edible film, 7 biosorbents, 8 and other composites. 9 Keratins have plenty of intermolecular and intramolecular cystine cross-links, which distinguishes them from other fibrous proteins such as collagen and myofibrillar protein.…”

Antistatic coatings for wood-floorings by imidazolium salt-based ionic liquids

“…All physical and spectroscopic data of the ILs used for the experiments were found to be in accordance to reported values [12][13][14][15][16][17][18][19][20][21].…”

“…Commercial 1-allyl-3-methylimidazolium chloride, CAS registry number [65039-10-3], was purchased from IoLiTec, Germany, or prepared by alkylation of 1-methylimidazole with allyl chloride according to published standard procedures [12]. Commercial 1-allyl-3-methylimidazolium tetrafluoroborate, CAS registry number [851606-63-8], was derived from 1-allyl-3-methylimidazolium chloride [65039-10-3] by extractive anion metathesis according to literature procedures [13,14].…”

Keratinous Materials as Novel Absorbent Systems for Toxic Pollutants

“…Therefore, aqueous solutions of chaotropic reagents such as urea or guanadinium hydrochloride are also needed to bring the bulk of the soluble proteins into solution [18][19][20] . There are reports of ionic liquids being used to solubilize keratin materials through breaking intermolecular disulfide and hydrogen bonds within keratin proteins [21][22][23][24][25] .…”