title: Dual-opposite-injection CZE: theoretical aspects and application to organic and pharmaceutical compounds.
abstract: Several important figures of merit (migration time, efficiency, resolution, resolution per unit time, and electrophoretic selectivity) are quantitatively compared for the first time for conventional CZE and dual-opposite-injection CZE (DOI-CZE). Aspects of DOI-CZE relevant to the separation of organic and pharmaceutical ions (MW>120 Da) are also discussed. Two new approaches to resolve the codetection of anions and cations, hydrodynamic flow-modified DOI-CZE and polarity reversal in combination with asymmetric detector window positioning, are compared with the method of preliminary transport, a variable procedure within sequential sample introduction, using a six-component sample of organic and pharmaceutical compounds. The advantages of DOI-CZE for the simultaneous analysis of organic/pharmaceutical anions and cations are illustrated in a direct comparison of conventional CZE and DOI-CZE for the separation of a ten-component mixture of pharmaceutical ions (five ionized acids and five ionized bases).
authors.affiliation: Analytical R&D, Pfizer Global Research and Development, Ann Arbor, MI, USA.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Weekley
authors.forename: Joe P
authors.initials: JP
authors.lastname: Foley
mesh_terms: D000838:Anions / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000379:methods*; D017022:Flow Injection Analysis / Q000379:methods*; D009930:Organic Chemicals / Q000302:isolation & purification*; D004364:Pharmaceutical Preparations / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D012996:Solutions / Q000737:chemistry
chemical_list: D000838:Anions; D002412:Cations; D009930:Organic Chemicals; D004364:Pharmaceutical Preparations; D012996:Solutions