title: Study of the retention behavior of small polar molecules on different types of stationary phases used in hydrophilic interaction liquid chromatography.
abstract: The retention behavior of a large group of analytes (35) with varied properties (pKa and logP) was studied on eight hydrophilic interaction LC columns with different surfaces, stationary phase chemistries, and types of particles. The acetonitrile content (5-95%), buffer concentration (0.5-200 mM), and pH of the mobile phase (3.8 and 6.8) were evaluated for their effects on the retention behavior. The type of stationary phase had a significant impact on the selectivity and retention time of the tested analytes. Completely different selectivity was observed on the aminopropyl stationary phase. In this study, the influence of the buffer concentration was similar for all tested columns, except for the aminopropyl stationary phase. Increasing the buffer concentration led to decreased retention times for the basic compounds and increased retention times for the acidic compounds, while the inverse behavior was observed on the aminopropyl stationary phase. The selectivity of the individual stationary phases was evaluated at pH 3.8 and 6.8. Much lower selectivity differences between the stationary phases were observed at pH 6.8 than pH 3.8. Bare silica stationary phases were used in the comparison of the particles (fused-core and fully porous particles of 3 and 1.7 μm) and the columns provided by different manufacturers.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague, Hradec Králové, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Vlčková
authors.forename: Kateřina
authors.initials: K
authors.lastname: Ježková
authors.forename: Kateřina
authors.initials: K
authors.lastname: Stětková
authors.forename: Helena
authors.initials: H
authors.lastname: Tomšíková
authors.forename: Petr
authors.initials: P
authors.lastname: Solich
authors.forename: Lucie
authors.initials: L
authors.lastname: Nováková
mesh_terms: D002853:Chromatography, Liquid / Q000295:instrumentation*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D009930:Organic Chemicals / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D009930:Organic Chemicals; D012822:Silicon Dioxide
keywords: Buffer concentration effects; Hydrophilic interaction liquid chromatography; Retention mechanisms; Stationary phases; pH effects