title: Reversed migration micellar electrokinetic chromatography with off-line and on-line concentration analysis of phenylurea herbicides.
abstract: Three environmentally important phenylurea herbicides (monuron, isoproturon, diuron) were separated in reversed migration micellar electrokinetic chromatography (RM-MEKC) using 50 mM sodium dodecyl sulfate, 50 mM phosphoric acid, and 15 mM gamma-cyclodextrin. Three on-line concentration techniques are then evaluated to increase the detection sensitivity of the RM-MEKC system. Stacking with reverse migrating micelles (SRMM, water as the sample solvent) provided the best results among the focusing techniques studied. Using a z-shaped detection cell, more than 500-fold increase in peak height is obtained. As a sample preparation and off-line concentration method, solid-phase extraction (SPE) that further improved detection sensitivity was used in the analysis of spiked tap and pond water. For example, 1 parts per billion of each herbicide spiked in tap or pond water was detected by MEKC after SPE and SRMM.
authors.affiliation: Faculty of Science, Himeji Institute of Technology, Kamigori, Hyogo, Japan.
authors.forename: J P
authors.initials: JP
authors.lastname: Quirino
authors.forename: N
authors.initials: N
authors.lastname: Inoue
authors.forename: S
authors.initials: S
authors.lastname: Terabe
mesh_terms: D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D006540:Herbicides / Q000032:analysis*; D010671:Phenylurea Compounds / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D006540:Herbicides; D010671:Phenylurea Compounds