Determination of Some Flavonoids in Scutellariae Radix by High-Performance Liquid Chromatography

Abstract

The determination of 7 kinds of flavonoids contained in Scutellariae Radix (ogon), i.e., baicalin, baicalein, wogonin 7-O-glucuronide, wogonin, skullcapflavone II, oroxylin A, and oroxylin A 7-O-glucuronide, was performed by high-performance liquid chromatography. These substances could be determined within about 40 min on a C-18 reversed-phase column. Elution was carried out with mixtures of methanol, acetic acid and water in ratios of 5 : 5 : 90 and 90 : 5 : 5 in the form of a gradient from 6 : 4 to 2 : 8.