Simultaneous determination of five marker constituents in Ssanghwa tang by HPLC/DAD

A HPLC-DAD method was established for the simultaneous evaluation of five bioactive compounds in Ssanghwa tang (SHT) including glycyrrhizin, paeoniflorin, cinnamic acid, decursin and 6-gingerol. These compounds were separated in less than 40 min using a Dionex C 18 column with a gradient elution system of water and methanol at a flow rate of 1 ml/min. Calibration curve of standard components presented excellent linear regression (R (2) > 0.9903) within the test range. Limit of detection and limit of quantification varied from 0.07 to 0.46 g/ml and 0.13 to 1.11 g/ml, respectively. The relative standard deviations (RSDs) of data of the intraday and interday experiments were less than 3.67 and 5.73, respectively. The accuracy of recovery test ranged from 95.98 to 105.88 with RSD values 0.10- 4.82.