Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan; Department of Chemistry, Jessore University of Science and Technology, Jessore 7408, Bangladesh.
Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
J Colloid Interface Sci. 2019 Sep 1;551:72-80. doi: 10.1016/j.jcis.2019.04.095. Epub 2019 May 2.
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 H and 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 (ΔG, ΔH, and ΔS) 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, [Cho][Ole] shows 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.
离子液体（IL）表面活性剂因其独特且有利的物理化学性质而备受关注，有望成为传统表面活性剂的替代品。然而，大多数 IL 表面活性剂并不环保，即使使用高浓度的表面活性剂，也会形成不稳定的胶束。在本研究中，我们制备了一系列不含卤素和生物相容的基于胆碱-脂肪酸的 IL，其链长和饱和度不同，然后研究了它们在水溶液中的胶束性质。通过氢核和碳核核磁共振波谱、傅里叶变换红外光谱、差示扫描量热法和元素分析对合成的表面活性 IL（SAIL）进行了表征。通过张力计、电导率计和动态光散射测量研究了 SAIL 的表面活性。发现 SAIL 的临界胶束浓度比传统表面活性剂低 2-4 倍。胶束化的热力学性质（ΔG、ΔH 和 ΔS）表明，在室温下，SAIL 的胶束化过程是自发的、稳定的和熵驱动的。通过哺乳动物细胞系 NIH 3T3 评估了 SAIL 的细胞毒性。重要的是，[Cho][Ole]比具有传统表面活性剂的类似 IL 显示出更低的毒性。这些结果清楚地表明，这些环保型 SAIL 可作为传统 IL 的潜在替代品，用于各种用途，包括生物应用。
