毛细管电泳法测定白芥子中芥子碱的含量

目的建立毛细管电泳法测定白芥子中芥子碱含量的方法。方法采用未涂层熔融石英毛细管柱(52 cm×100μm ID,有效分离长度42 cm)为分离通道,运行缓冲液为15 mmol.L-1柠檬酸-15mmol.L-1柠檬酸三钠(pH=5.0),操作电压15 kV(恒压),检测波长254 nm,毛细管柱温为25℃,电动进样7 kV×3 s。结果芥子碱硫氰酸盐质量浓度在0.5~20 mg.L-1内线性关系良好(r=0.998 9),平均加样回收率为97.8%(RSD值为2.36%,n=5)。白芥子中芥子碱的平均含量为4.23 mg.g-1,分析时间为5 min。结论用毛细管电泳法测定白芥子中芥子碱含量的方法可行、操作简单、检测快速。

Determination of the content of sinapine in seeds of Sinapis alba L. by capillary electrophoresis

Objective To develop the capillary electrophoresis method for quantitative analysis of sinapine in the seeds of Sinapis alba L.Methods A fused silica capillary(52 cm×100 μm ID,an effective length of 42 cm)was used.The running buffer was composed of 15 mmol·L-1 citric acid-15 mmol·L-1 sodium citrate(pH=5.0).The applied voltage was 15 kV and the capillary temperature was 25 ℃.The detection wavelength was set at 254 nm.The injection condition was 7 kV× 3 s.Results The content of sinapine in the seeds was 4.23 mg·g-1.The analysis time was 5 min.A good linearity was obtained in the range of 0.5-20 mg·L-1(r=998 9)for sinapine.The average recoveries and RSD were 97.3% and 2.72%(n=5),respectively.Conclusions The method is simple and rapid and it has satisfactory recoveries and good reproducibilities.