[HPLC determination of six flavonoid constituents in Ginkgo biloba leaves].

Six flavonoid constituents (quercetin, isorhamnetin, kaempferol, bilobetin, ginkgetin and sciadopitysin) were isolated from Ginkgo biloba leaves and determined by reversed phase HPLC using salvianolic acid B as internal standard. The column employed was Zorbax ODS (150 mm x 4 mm ID, 5 microns). The mobile phase consisted of solvent A (methanol) and solvent B [tetrahydrofuran--water--formic acid (34:65:1)] for gradient elution. The flow rate was 1 ml.min-1 and detection was effected at 350 nm. This method is accurate, rapid and reproducible. Analytical data for various samples were given.