Preparation and investigation of novel pyrrolidinium-bonded stationary phase for reversed-phase high-performance liquid chromatography .

A new ionic liquid-based high-performance liquid chromatography stationary phase is reported. A derivative of N-methyl pyrrolidinium tetrafluoroborate was covalently immobilized on the surface of silica particles to prepare silica-based N-methyl pyrrolidinium tetrafluoroborate (SilprMP BF4) stationary phase. The obtained ionic liquid-modified silica was evaluated and confirmed by elemental analysis, infrared spectroscopy, and thermogravimetric analysis. A column was packed with the modified particles. The retention behavior of aromatic compounds, alkyl benzenes, and acidic and basic compounds on the SilprMP BF4 stationary phase was studied under reversed-phase liquid chromatography conditions. The effect of the eluent pH on the separation of the acidic and basic compounds was also studied. The new stationary phase involves multiple retention mechanisms, such as electrostatic, hydrophobic, ion-dipole, and anion-exchange interactions, which might lead to multipurpose separation media.