title: Ionic liquids in enhancing the sensitivity of capillary electrophoresis: Off-line and on-line sample preconcentration techniques.
abstract: The popularity of ionic liquids (ILs) has grown during the last decade in enhancing the sensitivity of CE through different off-line or on-line sample preconcentration techniques. Water-insoluble ILs were commonly used in IL-based liquid phase microextraction, in all its variants, as off-line sample preconcentration techniques combined with CE. Water-soluble ILs were rarely used in IL-based aqueous two phase system (IL-ATPS) as an off-line sample preconcentration approach combined with CE in spite of IL-ATPS predicted features such as more compatibility with CE sample injection due to its relatively low viscosity and more compatibility with CE running buffers avoid, in some cases, anion exchange precipitation. Therefore, the attentions for the key parameters affecting the performance of IL-ATPSs were generally presented and discussed. On-line CE preconcentration techniques containing IL-based surfactants at nonmicellar or micellar concentrations have become another interesting area to improve CE sensitivity and it is likely to remain a focus of the field in the endeavor because of their numerous to create rapid, simple and sensitive systems. In this article, significant contributions of ILs in enhancing the sensitivity of CE are described, and a specific overview of the relevant examples of their applications is also given.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia.|Department of Chemistry, Faculty of Science, Assiut University, Assiut, Egypt.
authors.forename: Deia Abd
authors.initials: DA
authors.lastname: El-Hady
authors.affiliation: Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Hassan M
authors.initials: HM
authors.lastname: Albishri
authors.affiliation: Institute of Medicinal and Pharmaceutical Chemistry, TU Braunschweig, Braunschweig, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Wätzig
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods* / Q000592:standards; D052578:Ionic Liquids; D059627:Liquid Phase Microextraction / Q000379:methods; D008823:Micelles; D012680:Sensitivity and Specificity
chemical_list: D052578:Ionic Liquids; D008823:Micelles
keywords: Ionic liquids; Off-line preconcentration; On-line preconcentration; Sensitivity of CE