HPLC Determination of Emodin and Physcion in the TCM of “Runzao Zhiyang” Capsule

A method of HPLC for the determination of emodin and physcion in “Runzao Zhiyang” capsule was proposed. The sample was extracted with CH3OH-HCl (10+0.3) mixture and hydrolyzed for 30 min. The extracts were separated on Hypersil ODS 2 C18 column by gradient elution with mixtures of CH3OH and H3PO4-H2O (0.1+99.9) solution in different ratio, and determined at the wavelength of 254 nm. Values of average recovery found were 100.2% for emodin and 99.7% for physcion.