A retention model for polar selectivity in reversed phase chromatography as a function of mobile phase organic modifier type

Elucidation of solute retention as a function of the mobile phase modifier type under reversed phase conditions was investigated. The retention of steroid analogues were determined using methanol, acetonitrile, and tetrahydrofuran. Quantitative structure versus retention relationships (QSRRs) were then determined through the use of a de novo mathematical model. The results indicate that interactions between the solute and organic modifier that is extracted into the stationary phase play a significant role in the observed selectivity differences. Thermodynamic studies were conducted to further confirm the finding of the QSRRs determinations.