Choline chloride–thiourea, a deep eutectic solvent for the production of chitin nanofibers

• Published in: Carbohydrate polymers 2014-03, Vol.103, p.466-471
• Main Authors: Mukesh, Chandrakant, Mondal, Dibyendu, Sharma, Mukesh, Prasad, Kamalesh
• Format: Article
• Language: English
• Subjects: Applied sciences; Bio-nanocomposites; Biological and medical sciences; Chitin - chemical synthesis; Chitin - chemistry; Chitin nanofiber; Choline - chemistry; Composites; Deepeutectic solvents; Delivery; Drug slow; Exact sciences and technology; Forms of application and semi-finished materials; General pharmacology; Ionic liquids; Medical sciences; Nanofibers - chemistry; Natural polymers; Particle Size; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Physicochemistry of polymers; Polymer industry, paints, wood; Solvents - chemistry; Starch and polysaccharides; Surface Properties; Technology of polymers; Thiourea - chemistry
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2013.12.082

•Deep eutectic solvents were used for the production of chitin nanofibers.•The physicochemical properties of the nanofibers thus obtained were compared with those obtained using few ionic liquids.•The nanofibers thus obtained were used to prepare calcium alginate bio-nanocomposite gel beads.•The nanocomposite gel beads were used as sustained drug release application for an anticancer drug, 5-fluorouracil. Deep eutectic solvents (DESs) consisting of the mixtures of choline halide (chloride/bromide)–urea and choline chloride–thiourea were used as solvents to prepare α-chitin nanofibers (CNFs). CNFs of diameter 20–30nm could be obtained using the DESs comprising of the mixture of choline chloride and thiourea (CCT 1:2); however, NFs could not be obtained using the DESs having urea (CCU 1:2) as hydrogen bond donor. The physicochemical properties of thus obtained NFs were compared with those obtained using a couple of imidazolium based ionic liquids namely, 1-butyl-3-methylimidazolium hydrogen sulphate [(Bmim)HSO4] and 1-methylimidazolium hydrogen sulphate [(Hmim)HSO4] as well as choline based bio-ILs namely, choline hydrogen sulphate [(Chol)HSO4] and choline acrylate. The CNFs obtained using the DES as a solvent were used to prepare calcium alginate bio-nanocomposite gel beads having enhanced elasticity in comparison to Ca-alginate beads. The bio-nanocomposite gel beads thus obtained were used to study slow release of 5-fluorouracil, an anticancer drug.