Study of influence of ionic additives to AOT reverse microemulsions by liquid chromatography, IR and UV–visible spectroscopy

Reverse micellar mobile phases based on sodium bis(2-ethylhexyl) sulfosuccinate (AOT) were used as mobile phases in HPLC. The chromatographic behavior of the model compounds was studied on the basis of reverse micellar mobile phases modified by salt additives. Structural changes of water pools of reverse micelles depending from AOT concentration in the presence or absence of structure-making and structure-breaking ions was investigated by IR-Spectroscopy. The OH stretching vibrational absorption spectra in the region of 3000–3800 cm−1 were fitted into three subpeaks with a Monte Carlo method. The binding of o-nitroaniline (o-NA) to the micelles of AOT was determined by UV–visible spectroscopy. The different influence of kosmotropic and chaotropic anions on the binding constant Kb was revealed.