METHOD OF QUANTITATIVELY DETERMINING FLAVONOIDS BY DIFFERENTIAL VOLTAMMETRY TECHNIQUE Russian patent published in 2003 - IPC

FIELD: analytical methods. SUBSTANCE: method is proposed for analyzing trace amounts of flavonoids both in pure solutions and in chemically complex vegetable extracts, therapeutic forms, and pharmacological preparations. Flavonoids are transferred into solution by dissolving weighed sample in 70% ethanol on heating. Voltammetric measurements are carried out on glass-carbon electrode using reduction peaks at potentials between +0.41 and -0.63 v or oxidation peaks at potentials between -0.36 and +0.46 v against 0.2 N Na₂HPO₄ or 0.2 N C₆H₁₄O₇N₂. Differential-mode registration of peaks is performed at linear scanning velocity 20-30 mv/s. Concentration of quercitin, diquertin, menadione, and baikalin are determined from height of anodic or cathodic peaks. EFFECT: increased sensitivity, rapidity, and selectivity of determination. 5 cl, 2 tbl, 4 ex