title: Determination of isoflavones in red clover by capillary electrophoresis with electrochemical detection.
abstract: Capillary electrophoresis with electrochemical detection (CE-ED) was employed to analyze isoflavones in red clover (Trifolium pratense). The effects of potential of working electrode, pH and concentration of running buffer, separation voltage and injection time on CE-ED were investigated. Operated in a wall-jet configuration, a 300 microm diameter carbon-disk electrode was used as the working electrode, which exhibits a good response at +0.85 V (versus saturated calomel electrode) for the analytes. The analytes could be separated in a 50 mmol/l borate buffer (pH 9.5) within 25 min. The response was linear over three orders of magnitude with detection limit (S/N=3) ranging from 2x10(-5) mg/ml to 5x10(-5) mg/ml for the analytes. This method has been used for the determination of daidzein, genistein and biochanin A in red clover with satisfactory results.
authors.affiliation: Department of Chemistry, Quanzhou Normal University, Quanzhou, Fujian, 362000, China. youyuanpeng@hotmail.com
authors.forename: Y Y
authors.initials: YY
authors.lastname: Peng
authors.forename: J N
authors.initials: JN
authors.lastname: Ye
mesh_terms: D001881:Borates / Q000737:chemistry; D002021:Buffers; D002138:Calibration; D004563:Electrochemistry; D004566:Electrodes; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D019833:Genistein / Q000032:analysis / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007529:Isoflavones / Q000032:analysis* / Q000737:chemistry; D012044:Regression Analysis; D015203:Reproducibility of Results; D013997:Time Factors; D029921:Trifolium / Q000737:chemistry*
chemical_list: D001881:Borates; D002021:Buffers; D007529:Isoflavones; C004742:daidzein; D019833:Genistein; C004541:biochanin A