Eluotropic strength of solvents for parallel-displaced π–π interaction chromatography

A solvent eluotropic strength series for liquid chromatography in the parallel-displaced π–π interaction mode was established. Experiments were carried out on a pyrenylethyl group bonded stationary phase with 1,3-initrobenzene as a marker compound and a 40 : 60 isopropanol–n-hexane mixture as the initial mobile phase, in which 1, 3, 5, 10, 15 and 20% were replaced by the solvent under study.