Modification of the murakami retention model in reversed-phase high-performance liquid chromatography for micellar chromatographic separations

A retention model for micellar liquid chromatography was tested based on the data of separation of three benzodiazepins and six β-blockers. The model was obtained by analyzing changes in the microenvironment of a sorbate in transferring from the mobile to stationary phase. It can be used to describe the retention of benzodiazepins, which are neutral under the separation conditions, and the positively charged β-blockers. The calculated model coefficients are indicative of an increase in the number of 1-pentanol molecules and sodium dodecyl sulfate monomers in the microenvironment of the sorbates in transferring from the mobile to stationary phase. The solvation of the positive β-blockers by anionic surfactant monomers was higher than that of neutral benzodiazepins.