Content Determination and Stability of Koumine by UPLC

OBJECTIVE To establish a ultra high performance liquid chromatography(UPLC) method for determination of koumine and to study the stability of koumine solution at room temperature. METHODS The analysis was achieved by Agilent Extend-C₁₈ chromatogram column(2.1 mm×100 mm, 1.8 μm). The mobile phase composed of acetonitrile-0.2% butylamine (30∶70) at flow rate of 0.5 mL?min^-1. The detection wavelength was set at 256 nm. Three batches of koumine were determined and stability of its solution was examined under room temperature. RESULTS Under the estabilished method, the separation of koumine and its main related substances was good. The linear range of koumine was 10.19-112.2 μg?mL^-1(r=0.999 7) with detection limit of 0.1 μg?mL^-1. The average recovery was 100.4% (RSD=0.45%, n=9). The average concentration of koumine were 99.97%(n