Simultaneous HPLC Determination of 5 Active Components in the TCM of “Gezhi” Capsule

A method of HPLC for the determination of 5 active components, including puerarin, daidzin, liquiritin, daidzein and glycyrrhizic acid, in the TCM “Gezhi” capsule was proposed. The sample was extracted with mixture of methanol and H2O (50+50) for 30 min. The extract was separated on Diamonsil C18 column (200 mm×4.6 mm, 5 μm) by gradient elution with mixtures of methanol and dil. phosphoric acid (0.1+99.9) solution in different ratios, and determined at the wavelength of 250 nm except for liquirtin at 276 nm. Linear relationships between peak area and mass concentration of the 5 active components were kept in the definite ranges, with detection limits (3S/N) in the range of 0.050-0.338 mg·L-1. Values of average recovery of the method found were in the range of 97.1%-104% and RSD′s (n=6) found were in the range of 1.0%-2.7% respectively.