Preparation and evaluation of silica-based N-octylimidazolium stationary phases for HPLC

Abstract

In this study, a new silica-based N-octylimidazolium bromide stationary phase, SilprOIm Br, has been synthesized, and then the stationary phase's anion has been converted to tetrafluoroborate to provide a new silica-based N-octylimidazolium tetrafluoroborate stationary phase, SilprOIm BF₄. The modified particles were characterized by thermogravimetric analysis (TGA) and elemental analysis. Columns were packed with stationary phases. They were tested under HPLC conditions. The new phases indicated multiple retention mechanisms, such as anion-exchange, hydrophobic interaction, electrostatic interaction and π–π interaction, which may lead to more universally applicable separation media. Furthermore, the effect of the stationary phase's anion on the separation of compounds has been investigated.