ABSTRACT:
Hydrophilic Interaction Liquid Chromatography (HILIC) is a variant of normal phase chromatography that performed with a very polar stationary phase and a mostly organic mobile phase. When the mobile phase contains > 60% organic solvent, then hydrophilic interaction becomes significant. The mechanism of HILIC implicates partitioning between a water-enriched layer partially immobilized on the hydrophilic stationary phase and the less polar mobile phase. A chromatographic system for HILIC chromatography is essentially instrumental identical to RPLC (Reversed Phase Liquid Chromatography) systems. HILIC columns contain a stationary phase that is hydrophilic and quite often also charged, at least in some region of the pH-scale. Compounds separated on the column interact with the stationary phase and are generally more strongly retained the more hydrophilic the compound. It is used for determination of dimethindene maleate in topical gel, zanamivir in rat and monkey plasma, tromethamine as the counter ion in an investigational pharmaceutical salt.