Simultaneous HPLC Determination of Four Active Components in Sucking Tablets of “Caoshanhu” Compound

HPLC was applied to the determination of 4 activitive components, namely, procatechuic acid, 3-hydroxy-4-methoxy benzoic acid, isofraxindin and rosmarinic acid, in sucking tablets of “Caoshanhu” compound. The sample was extracted ultrasonically with methanol and the extract was used for the determination. Water SunFire ODS column (4.6 mm×150 mm, 5 μm) was used as stationary phase, and mixtures of acetonitrile and phosphoric acid (0.1+99.9) solution in various ratios were used as mobile phase in gradient elution with flow-rate of 0.8 mL·min-1. Wavelength of 294 nm was chosen for UV-detection of the 4 components. Under optimum chromatographic conditions, linearity ranges were obtained between 2.508-50.16 ng (for procatechuic acid), 18.40-368.0 ng (for 3-hydroxy-4-methoxy benzoic acid), 6.375-127.5 ng (for isofraxindin) and 41.04-820.8 ng (for rosmarinic acid). Values of average recovery found were 92.8%,93.1%, 91.9% and 99.6% respectively. Values of RSD′s (n=6) found were less than or equal to 5.0%.