title: Separation and determination of flavonoids using microemulsion EKC with electrochemical detection.
abstract: A selective and sensitive method of microemulsion EKC (MEEKC) with electrochemical detection (ED) was developed for separation and determination of 14 flavonoids. In order to obtain the better stability for the studied flavonoids, oil (ethyl acetate) with low interfacial surface tension was employed as organic solvent. A running buffer composed of 0.9% (w/v, 30 mM) SDS, 0.9% (w/v, 21 mM) sodium cholate (SC), 0.9% (w/v, 121 mM) butan-1-ol, 0.6% (w/v, 68 mM) ethyl acetate, and 98.2% v/v 10 mM Na(2)B(4)O(7)-20 mM H(3)BO(3) buffer (pH 7.5) was applied for the separation of flavonoids. Under the optimum conditions, the relationship between peak currents and analyte concentrations was linear over about 1.3 and 1.7 orders of magnitude with detection limits (defined as S/N = 3) ranging from 0.02 to 0.5 microg/mL for all analytes. This method was applied for the determination of flavonoids in real samples with simple extraction procedures, and the assay results were satisfactory.
authors.affiliation: Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Fuzhou University, Fuzhou, Fujian, P R China.
authors.forename: Li-Shuang
authors.initials: LS
authors.lastname: Yu
authors.forename: Xue-Qin
authors.initials: XQ
authors.lastname: Xu
authors.forename: Lu
authors.initials: L
authors.lastname: Huang
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Ling
authors.forename: Guo-Nan
authors.initials: GN
authors.lastname: Chen
mesh_terms: D019659:Asteraceae / Q000737:chemistry; D002021:Buffers; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods* / Q000706:statistics & numerical data; D004563:Electrochemistry; D004655:Emulsions; D005419:Flavonoids / Q000032:analysis / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D015203:Reproducibility of Results; D012838:Silymarin / Q000737:chemistry; D013501:Surface-Active Agents
chemical_list: D002021:Buffers; D004655:Emulsions; D005419:Flavonoids; D012838:Silymarin; D013501:Surface-Active Agents