CSEI-sweep cationic selective exhaustive

CSEI-sweep cationic selective exhaustive injection-sweeping... 

Combinations of online procedures are often employed in environmental applications. Examples include the analysis of trace metal ions in factory wastewater by a combination of cation-selective exhaustive injection (CSEI) (a form of stacking, CZE format) and sweeping. In this latter case, sweeping was promoted by dynamic complexation with EDTA, used as carrier. The same CSEI principle has also been applied to the analysis of quaternary ammonium herbicides and environmentally relevant aromatic amines in water, both followed by sweeping with SDS. 

Cation- and anion-selective exhaustive injection sweeping (CSEI-sweep and ASEI-sweep) techniques are also available in MEKC. CSEI-sweep and ASEI-sweep are combinations of two online preconcentration techniques, sample stacking with electrokinetic injection and sweeping, that can provide more than 100,000-fold enhancements in detection sensitivity. An electropherograms of tap water analysis by CSEI-sweep-MEKC is illustrated in Figure 7. The results of this study suggest that CSEI-sweep-MEKC can be used for the analysis of quaternary ammonium herbicides in drinking water. 

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