RESUMEN
Objective:To develop a method for simultaneous determination of the contents of geniposide, hesperidin, baicalin, liquiritin, glycyrrhetinic acid, glycyrrhizic and schizandrin in Ermu-Ningsou Pills by ultra performance liquid chromatography (UPLC) with wavelength switching. Methods:The analyses were carried out on an Phenomenex Kinetex C18 column (4.6 mm×100 mm, 2.7 μm) with the mobile phase consisting of methanol(A)-0.05% phosphoric acid (B) in a gradient mode at a flow rate of 0.6 ml/min. The detection wavelength was set at 237 nm for geniposide, liquiritin, glycyrrhetinic acid and glycyrrhizic, 280 nm for baicalin and hesperidin, 250 nm for schizandrin. The column temperature was set at 35 ℃ and the injection volume was 2 μl.Results:The linear relation of geniposide, hesperidin, baicalin, liquiritin, glycyrrhetinic acid, glycyrrhizic and schizandrin were excellent within the range of 10.294-205.888, 4.552-91.036, 6.212-124.248, 8.974-179.484, 2.629-52.580, 5.371-107.416, 8.905-178.104 ng ( r≥0.999 5, n=6). Average recoveries were 98.47%, 99.04%, 100.76%, 98.27%, 100.50%, 98.79%, 99.37% ( RSD<2.0%, n=6). RSDs of precision, reproducibility and stability tests (24 h) were lower than 2.0% ( n=6). Conclusions:The method is simple, effective, accurate. It can be used for simultaneous determination of 7 active constituents in Ermu-Ningsou Pills.