RP-HPLC测定苦豆子总碱中莱曼碱的含量___

Objective:To develop an RP-HPLC method for the determination of lehmannine in total alkaloids of Sophora alopecuroides. Methods:The samples were analyzed on a Kromasil 100-5C₁₈ column(250 mm×4.6 mm,5 μm) with acetonitrile-a mixture of 0.03 mol·L^-1 ammonium dihydrogen phosphate containing 1.0 mL phosphoric acid and adjusting pH 5 with triethylamine (70∶30) as mobile phase.The flow rate was 1.0 mL·min^-1, and UV detection wavelength was 205 nm. Results: The linear range of lehmannine was in the range of 0.47-1.40 μg(r=0.9999). The recovery(n=6) was 99.4% with RSD of 1.7%, and the precision of lehmannine was RSD=1.1%(n=5). The relative contents of lehmannine in three batches of total alkaloids of Sophora alopecuroides were 1.8%, 2.1%, and 1.6% respectively. Conclusion:The new method is fast, accurate, sensitive, selective, and suitable for the quality control of total alkaloids of Sophora alopecuroides.