High Submicellar Liquid Chromatography

摘要

Surfactant addition above the critical micellar concentration (CMC), in reversed-phase liquid chromatography (RPLC), was proposed as a way to modify the selectivity and analysis time, giving rise to a chromatographic mode called micellar liquid chromatography (MLC). However, solutions containing only surfactant are too weak and yield poor peak shape. This was remediated by the addition of a small amount of organic solvent. To preserve the existence of micelles, in MLC high contents of organic solvent are avoided. Nevertheless, there is no reason to neglect the potentiality of mobile phases containing a surfactant above its CMC in water and a high organic solvent content (without micelles). This chromatographic mode has been called high submicellar liquid chromatography (HSLC). Several reported procedures show that the combination of stronger elution strength, larger selectivity and improved peak shape, with respect to MLC and conventional RPLC, makes HSLC a promising chromatographic mode to achieve in practical times separations of compounds unresolved or highly retained with other RPLC modes. Some insights on the interactions that occur inside the chromatographic column, the modification of the stationary and mobile phases, retention modeling, and chromatographic performance in HSLC are here offered, in comparison to MLC and conventional RPLC.