Quantitative determination of 14 major constituents in the herbal preparation Luan-Pao-prescription using HPLC coupled with photodiode array detection

High performance liquid chromatography coupled with photodiode array detection (HPLC-DAD) was employed for the determination of 14 major constituents in traditional Chinese herbal formula 'Luan-Pao-Prescription'. Two different chromatographic determinations for the 14 constituents were carried out to control the quality of this herbal formula. The sample was extracted under ultrasonic extraction with 75% methanol at the frequency of 42 kHz for 45 min at room temperature. The chromatographic separation was performed on a Zorbax SB-C₁₈. The mobile phase was linear gradient elution of water with 0.5% (v/v) acetic acid (A) and acetonitrile (B) column with linear gradient elution procedure. The flow rate was set at 1.0 mL min^-1 and the column temperature was kept at 30°C. The calibration curve for the determination of all the analytes showed good linearity over the investigated ranges (R ² > 0.999). The intra- and inter-day assay precision (RSD) of 14 analytes were in the range of 0.2-3.9% and the recoveries were between 92.4 and 104.4%. The validated method was successfully applied to the determination of 14 major constituents in LPP.