Characterization of a novel pyridinium bromide surface confined ionic liquid stationary phase for high-performance liquid chromatography under normal phase conditions via linear solvation energy relationships

Abstract

Utilizing Linear Solvation Free Energy Relationship methodology, a novel pyridinium bromide surface confined ionic liquid (SCIL) stationary phase was characterized under normal phase High Performance Liquid Chromatographic conditions. A limited set of neutral aromatic probe solutes were utilized to rapidly assess the utility of the LSER model, using mobile phases of hexane modified with 2-propanol. The excellent correlation of the global fit across the mobile phase composition range used in this study for the experimental and calculated retention values (R 2 = 0.994) indicates that the LSER model is an appropriate model of characterizing this polar bonded phase under normal phase conditions. For a limited subset of compounds, retention on the pyridinium bromide SCIL stationary phase is more highly correlated with that obtained on a cyano column than on a diol column under NP conditions.

Application of ionic liquids as mobile phase additives and surface-bonded stationary phase in liquid chromatography

“…A new anion-exchange stationary phase was made based on Nmethylimidazolium through the reaction of activated silica with 3-chloropropyltrimethoxysilane and subsequently with N-methylimidazole [26]. Using this new stationary phase, familiar inorganic anions, organic anions and some other organic compounds were separated successfully.…”

Versatile ligands for high-performance liquid chromatography: An overview of ionic liquid-functionalized stationary phases

“…Among these studies, an exhaustive characterization of pyridinium-based phase reported by Van Meter et al was of great interest [64]. The pyridinium cation was tethered to silica by quaternization of pyridine with 8-bromooctyltrimethoxysilane.…”

Preparative isolation of flavonoid compounds from Oroxylum indicum by high‐speed counter‐current chromatography by using ionic liquids as the modifier of two‐phase solvent system

“…Especially in the field of separation science, ionic liquids can be used as organic modifiers in HPLC [6], ideal candidates for stationary phases of GC [7] and BGEs in CE [8] or EKC [9]. Moreover, applications of chiral ionic liquids in separation procedure make it possible for separation of some enantiomers [10].…”