relation: https://khub.utp.edu.my/scholars/11375/ title: Synthesis and characterization of choline�fatty-acid-based ionic liquids: A new biocompatible surfactant creator: Ali, M.K. creator: Moshikur, R.M. creator: Wakabayashi, R. creator: Tahara, Y. creator: Moniruzzaman, M. creator: Kamiya, N. creator: Goto, M. description: Ionic liquid (IL)surfactants have attracted great interest as promising substitutes for conventional surfactants owing to their exceptional and favorable physico-chemical properties. However, most IL surfactants are not eco-friendly and form unstable micelles, even when using a high concentration of the surfactant. In this study, we prepared a series of halogen-free and biocompatible choline�fatty-acid-based ILs with different chain lengths and degrees of saturation, and we then investigated their micellar properties in aqueous solutions. Characterization of the synthesized surface-active ILs (SAILs)was performed by 1 H and 13 C nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and elemental analysis. The surface-active properties of the SAILs were investigated by tensiometry, conductometry, and dynamic light scattering measurements. The critical micelle concentration of the SAILs was found to be 2�4 times lower than those of conventional surfactants. The thermodynamic properties of micellization (�G 0 m , �H 0 m , and �S 0 m )indicate that the micellization process of the SAILs is spontaneous, stable, and entropy-driven at room temperature. The cytotoxicity of the SAILs was evaluated using mammalian cell line NIH 3T3. Importantly, ChoOleshows lower toxicity than the analogous ILs with conventional surfactants. These results clearly suggest that these environmentally friendly SAILs can be used as a potential alternative to conventional ILs for various purposes, including biological applications. © 2019 Elsevier Inc. publisher: Academic Press Inc. date: 2019 type: Article type: PeerReviewed identifier: Ali, M.K. and Moshikur, R.M. and Wakabayashi, R. and Tahara, Y. and Moniruzzaman, M. and Kamiya, N. and Goto, M. (2019) Synthesis and characterization of choline�fatty-acid-based ionic liquids: A new biocompatible surfactant. Journal of Colloid and Interface Science, 551. pp. 72-80. ISSN 00219797 relation: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85065148168&doi=10.1016%2fj.jcis.2019.04.095&partnerID=40&md5=3e161dca7d2f424c64c9e96c270e152c relation: 10.1016/j.jcis.2019.04.095 identifier: 10.1016/j.jcis.2019.04.095