title: Thousand fold concentration of an alkaloid in capillary zone electrophoresis by micelle to solvent stacking.
abstract: In this paper, the co-solvent of methanol-water was used to facilitate the sodium dodecyl sulfate (SDS) micelles collapse, thereby inducing the on-line sample focusing technique of micelle to solvent stacking (MSS). To demonstrate this stacking method, the mechanism of micelles collapse in co-solvent was discussed. The details of the required conditions were investigated and the optimized conditions were: running buffer, 20mM H(3)BO(3) and 20mM NaH(2)PO(4) solution (pH 4.0); micellar sample matrix, 20mM SDS, 20mM H(3)BO(3) and 20mM NaH(2)PO(4) solution (pH 4.0); co-solvent buffer, 20mM H(3)BO(3) and 20mM NaH(2)PO(4) in methanol/water (90:10, v/v). The validity of the developed method was tested using cationic alkaloid compounds (ephedrine and berberine) as model analytes. Under the optimized conditions, this proposed method afforded limits of detection (LODs) of 0.5 and 1.1ng/mL with 300 and 1036-fold improvements in sensitivity for ephedrine and berberine, respectively, within 15min.
authors.affiliation: Department of Chemistry, Lanzhou University, Lanzhou 730000, China.
authors.forename: Hua-dong
authors.initials: HD
authors.lastname: Zhu
authors.forename: Cui-ling
authors.initials: CL
authors.lastname: Ren
authors.forename: Shao-qiang
authors.initials: SQ
authors.lastname: Hu
authors.forename: Xi-min
authors.initials: XM
authors.lastname: Zhou
authors.forename: Hong-li
authors.initials: HL
authors.lastname: Chen
authors.forename: Xing-guo
authors.initials: XG
authors.lastname: Chen
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification / Q000652:urine; D001599:Berberine; D019075:Electrophoresis, Capillary / Q000379:methods*; D004809:Ephedrine; D006801:Humans; D016014:Linear Models; D008823:Micelles; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012967:Sodium Dodecyl Sulfate
chemical_list: D000470:Alkaloids; D008823:Micelles; D001599:Berberine; D012967:Sodium Dodecyl Sulfate; D004809:Ephedrine