Shankar B Vijai, Patnaik Archita
Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
Langmuir. 2007 Mar 27;23(7):3523-9. doi: 10.1021/la061651x. Epub 2007 Mar 3.
Enantiomeric, twin-tailed, twin-chiral, sodium (2R,3R)-(+)-bis(decyloxy)succinate and sodium (2S,3S)-(-)-bis(decyloxy)succinate have been synthesized and characterized. Surface tension, conductivity, and steady-state fluorescence spectroscopic measurements confirmed the presence of two aggregation concentrations, namely, the critical micellar concentration (CMC) and the critical vesicle concentration (CVC). The compounds behaved as true surfactants, with a CMC of 0.05 mM, and formed vesicles spontaneously in aqueous solution at a CVC of 0.14 mM. The compounds formed myelin figures in contact experiments, suggesting the formation of bilayers in aqueous solution culminating into individual vesicles. The vesicles were of 500-800 nm size and formed egg shells, porous spheres, and multivesicular vesicles, confirmed from transmission electron microscopy and optical microscopic techniques. The vesicles were found to be pH sensitive, were stable in the pH range 6-8, and formed the insoluble diacid at acidic pH due to protonation of the carboxylate head groups.
对映体、双尾、双手性的(2R,3R)-(+)-双(癸氧基)琥珀酸钠和(2S,3S)-(-)-双(癸氧基)琥珀酸钠已被合成并表征。表面张力、电导率和稳态荧光光谱测量证实存在两个聚集浓度，即临界胶束浓度(CMC)和临界囊泡浓度(CVC)。这些化合物表现为真正的表面活性剂，CMC为0.05 mM，并在水溶液中以0.14 mM的CVC自发形成囊泡。在接触实验中，这些化合物形成了髓鞘样结构，表明在水溶液中形成了双层结构，最终形成单个囊泡。囊泡大小为500 - 800 nm，形成了蛋壳状、多孔球体和多囊泡，这通过透射电子显微镜和光学显微镜技术得到证实。发现这些囊泡对pH敏感，在pH值6 - 8范围内稳定，并且由于羧酸根基团的质子化在酸性pH下形成不溶性二酸。
