RESUMO
Objective:To establish an HPLC method for the determination of promethazine hydrochloride and glycyrrhizic acid in compound promethazine and glycyrrhizae oral solution. Methods:A Thermo BDS C18 column(250 mm × 4. 6 mm,5μm)was used with methanol-glacial acetic acid-0. 2 mol·L-1 ammonium acetate solution (58: 1: 41)as the mobile phase. The flow rate was 1. 0 ml· min-1 and the detection wavelength was 250 nm. The column temperature was ambient and the injection volume was 10 μl. Results:There was a good linear relationship within the concentration range of 0. 079 4-0. 317 6 mg · ml-1 ( r =0. 999 9 ) for promethazine hydrochloride and 0. 060 3-0. 241 1 mg · ml-1 ( r =0. 999 9 ) for glycyrrhizic acid. The average recovery was 99. 61% ( RSD =0. 32%, n=9) and 99. 30% (RSD=0. 59%, n=9), respectively. Conclusion: The method is simple, accurate and repeatable, which can be used to control the quality of the preparation.