title: On-line simultaneous and rapid separation of anions and cations from a single sample using dual-capillary sequential injection-capillary electrophoresis.
abstract: A novel capillary electrophoresis (CE) approach has been developed for the simultaneous rapid separation and identification of common environmental inorganic anions and cations from a single sample injection. The method utilised a sequential injection-capillary electrophoresis instrument (SI-CE) with capacitively-coupled contactless conductivity detection (C(4)D) constructed in-house from commercial-off-the-shelf components. Oppositely charged analytes from a single sample plug were simultaneously injected electrokinetically onto two separate capillaries for independent separation and detection. Injection was automated and may occur from a syringe or be directly coupled to an external source in a continuous manner. Software control enabled high sample throughput (17 runs per hour for the target analyte set) and the inclusion of an isolation valve allowed the separation capillaries to be flushed, increasing throughput by removing slow migrating species as well as improving repeatability. Various environmental and industrial samples (subjected only to filtering) were analysed in the laboratory with a 3 min analysis time which allowed the separation of 23 inorganic and small organic anions and cations. Finally, the system was applied to an extended automated analysis of Hobart Southern Water tap water for a period of 48 h. The overall repeatability of the migration times of a 14 analyte standard sample was less than 0.74% under laboratory conditions. LODs ranged from 5 to 61 μg L(-1). The combination of automation, high confidence of peak identification, and low limits of detection make this a useful system for the simultaneous identification of a range of common inorganic anions and cations for discrete or continuous monitoring applications.
authors.affiliation: Australian Centre for Research on Separation Science (ACROSS), School of Chemistry, Faculty of Science Engineering and Technology, University of Tasmania, Hobart, Tasmania 7001, Australia.
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Gaudry
authors.forename: Rosanne M
authors.initials: RM
authors.lastname: Guijt
authors.forename: Mirek
authors.initials: M
authors.lastname: Macka
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Hutchinson
authors.forename: Cameron
authors.initials: C
authors.lastname: Johns
authors.forename: Emily F
authors.initials: EF
authors.lastname: Hilder
authors.forename: Greg W
authors.initials: GW
authors.lastname: Dicinoski
authors.forename: Pavel N
authors.initials: PN
authors.lastname: Nesterenko
authors.forename: Paul R
authors.initials: PR
authors.lastname: Haddad
authors.forename: Michael C
authors.initials: MC
authors.lastname: Breadmore
mesh_terms: D000838:Anions / Q000032:analysis*; D002412:Cations / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D008670:Metals / Q000032:analysis; D009862:Online Systems; D015203:Reproducibility of Results; D012984:Software; D014867:Water / Q000032:analysis
chemical_list: D000838:Anions; D002412:Cations; D008670:Metals; D014867:Water