title: Use of coupled open-tubular capillaries for in-line ion-exchange preconcentration of anions by capillary electrochromatography with elution by a transient isotachophoretic gradient.
abstract: Open-tubular capillaries have been joined together for use in on-column ion-exchange preconcentration of anions by capillary electrochromatography (CEC) with elution by a transient isotachophoretic gradient. This involved the coupling of a preconcentration capillary and a separation capillary using a PTFE sleeve. Such coupling allowed precise lengths of differently coated capillaries to be joined in-line to form a single multi-mode column. The different segments could be tailored to optimize a separation by either altering the length of each segment to precisely manipulate the amount of stationary phase present or by changing the internal diameter of each segment to alter the phase ratio in the chromatographic column without affecting the path length for UV detection. In this work, a segmented in-line capillary was used in conjunction with a fluoride-octanesulfonate discontinuous electrolyte system to increase the number of anions that could be preconcentrated and separated. Quaternary ammonium functionalised latex particles were used for creating the preconcentration segment and the separation segment was coated with poly(diallyldimethylammonium chloride). This allowed the detection of trace anions in drinking water and in situ sampling of river water for the analysis of trace inorganic anions. The repeatability of producing the quaternary ammonium functionalized latex-coated segments was assessed and the effect of segmentation on peak efficiency was investigated.
authors.affiliation: Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, Private Bag 75, Hobart 7001, Australia.
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Hutchinson
authors.forename: Miroslav
authors.initials: M
authors.lastname: Macka
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Avdalovic
authors.forename: Paul R
authors.initials: PR
authors.lastname: Haddad
mesh_terms: D000838:Anions / Q000032:analysis*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000295:instrumentation*; D004586:Electrophoresis / Q000379:methods*; D007475:Ion Exchange Resins
chemical_list: D000838:Anions; D007475:Ion Exchange Resins