Simultaneous Determination of the Five Marker Compounds in Melandriumfirmum using High-Performance Liquid Chromatography with Photodiode-Array Detection.

In Korean folk medicine, Melandrium firmum Rohrbach (Caryophyllaceae) has been used to treat various diseases, including anuria, breast cancer, and gonorrhea. In this study, a high-performance liquid chromatography method with photodiode-array UV detection (HPLC-PDA) was established and then validated for the simultaneous determination of five flavonoids in M firnum: schaftoside, homoorientin, cytisoside, vitexin, and isovitexin. Separation of the five compounds was performed on a Gemini C18 column at 40'C by gradient elution of two mobile phases. The flow rate and injection volume were 1.0 m/min and 10 pL, respectively. The HPLC-PDA method showed excellent linear regression with r2 values of 0.9999 within the test ranges. The limits of -detection and quantification of all components were 0.01-0.11 and 0.04-0.34 pg/mL, respectively. The extraction recovery of the five analytes was 97.6-- 105.6% and the RSD values were < 2.0%. The relative standard deviation values of intra- and interday precision for all analytes were < 1.71 and < 1.46%,. respectively. As determined using the established and validated HPLC-PDA method described here, the amounts of the five marker compounds in M firmuin .were 0.02-2.54 mg/g.