title: On-line sample concentration in micellar electrokinetic chromatography using cationic surfactants.
abstract: Two on-line sample concentration techniques, sample stacking and sweeping, were evaluated using cationic surfactants as pseudostationary phases in micellar electrokinetic chromatography. As cationic surfactant micelles, tetradecyltrimethylammonium bromide and cetyltrimethylammonium chloride were employed. About 10-fold and 1000-fold increases in detection sensitivity in terms of peak heights were observed by sample stacking and sweeping, respectively, without suppression of the electroosmotic flow. In particular, the concentration limits of detection (S/N=3) for test naphthalenesulfonic acids obtained with sweeping were from 0.96 to 0.47 ppb with UV detection without any preconcentration procedure.
authors.affiliation: Faculty of Science, Himeji Institute of Technology, Kamigori, Hyogo, Japan. jbkim@sci.himeji-tech.ac.jp
authors.forename: J B
authors.initials: JB
authors.lastname: Kim
authors.forename: J P
authors.initials: JP
authors.lastname: Quirino
authors.forename: K
authors.initials: K
authors.lastname: Otsuka
authors.forename: S
authors.initials: S
authors.lastname: Terabe
mesh_terms: D002412:Cations / Q000737:chemistry; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet; D013501:Surface-Active Agents / Q000737:chemistry*; D050337:Trimethyl Ammonium Compounds
chemical_list: D002412:Cations; D002593:Cetrimonium Compounds; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents; D050337:Trimethyl Ammonium Compounds; C009410:tetradecyltrimethylammonium; D000077286:Cetrimonium