Identification and determination of ecdysone and phenylpropanoid glucoside and flavonoids in Lamium maculatum by carpillary zone electrophoresis

The simultaneous determination of 20-hydroxy ecdysone (1), 3,7-dimethoxy-quercetin (2), acteoside (3) and rutin (4) in the mixture of leaf and stem, and the flower of Lamium maculatum has been investigated by capillary zone electrophoresis for the first time. With an electrolyte containing 30 mmol/L borate, at pH 9.47 and 20 kV applied voltage, the four active compounds were completely separated within 5 min with satisfactory results. The effects of concentration of borate and electrolyte pH on electrophoretic behavior and separation were studied. Regression equations revealed linear relationships (correlation coefficients 0.9998-0.9999) between the peak area of each analyte and the concentration. The levels of analytes in the different parts of Lamium maculatum were easily determined with recoveries ranging from 98.3 to 105.0%. Copyright (C) 2003 John Wiley Sons. Ltd.