作者:Juan V. Trillo、Francisco Meijide、José Vázquez Tato、Aida Jover、Victor H. Soto、Santiago de Frutos、Luciano Galantini
DOI:10.1039/c3ra45543b
日期:——
New double-chain surfactants can be designed in which nitrilotriacetic acid plays the role of glycerol in phospholipids. The synthetic methodology is applied to the synthesis of (2-(bis(2-dodecylamino)-2-oxoethyl)amino)acetic acid. This is a symmetric dimeric surfactant but the methodology allows the synthesis of asymmetric double-chain surfactants as well. The Krafft temperature is 16–18 °C. The critical aggregation concentration of the new surfactant (4.76 × 10−5 mol dm−3 in NaOH 0.01 M and 25 °C; surface tension measurements) is two hundred times lower than that for sodium 2-dodecanamidoacetate, which can be considered its monoalkyl surfactant analog, indicating the enhanced surfactant properties resulting from the presence of two hydrophobic alkyl chains. The shape of the aggregates was investigated by transmission electron microscopy. At 40 °C, the main structure present in solution corresponds to vesicles and, from the size distribution of their radii, values of (0.34 ± 0.06)kT and 56.7 ± 2.6 nm were obtained for the effective bending elasticity constant and the spontaneous radius of curvature of vesicles, respectively.
可以设计出新的双链表面活性剂,其中次氮基三乙酸在磷脂中扮演甘油的角色。该合成方法应用于合成(2-(双(2-十二烷基氨基)-2-氧代乙基)氨基)乙酸。这是一种对称二聚表面活性剂,但该方法也可以合成不对称双链表面活性剂。克拉夫特温度为 16-18 °C。这种新型表面活性剂的临界聚集浓度(4.76 × 10-5 mol dm-3,NaOH 0.01 M,25 °C;表面张力测量值)比可视为其单烷基表面活性剂类似物的 2-十二酰胺基乙酸钠的临界聚集浓度低 200 倍,这表明由于存在两条疏水烷基链,表面活性剂的性能得到了增强。透射电子显微镜研究了聚合体的形状。在 40 °C 时,溶液中存在的主要结构是囊泡,从其半径的大小分布来看,囊泡的有效弯曲弹性常数和自发曲率半径的值分别为 (0.34 ± 0.06)kT 和 56.7 ± 2.6 nm。