高效液相色谱法测定饲料中左旋咪唑

Determination of levamisole in feeds by High performance liquid chromatography

本实验建立了高效液相色谱法检测配合饲料和浓缩饲料中左旋咪唑的方法。样品在碱性水溶液中用乙酸乙酯提取，正己烷除脂净化；采用SCX（5μm，250mm×4．6mm.i．d．）色谱柱分离，流动相为0．02mol／L磷酸二氢钠-乙腈溶液（75：25，V／V），紫外检测波长215nm。结果显示，左旋咪唑浓度为0．1—50μg／mL时呈现良好的线性关系，线性方程为Y=127．5C＋1．973（r〉0．9999）。该方法在不同添加浓度下，回收率为80％～110％，批内变异系数和批间变异系数均小于10％。左旋咪唑在配合饲料中的检测限为0．2mg／kg，定量限为0．5mg／kg；在浓缩饲料中的检测限为0．4mg／kg，定量限为1mg／kg。

A high-performance liquid chromatography （HPLC） method for determination of levamisole in feed was described in this paper.The samples were extracted by ethyl acetate in alkaline water solution, and get rid of fat by n-hexane.The reconstitued samples were transferred to HPLC system to be detected using the SCX column（5 μm,250 mm×4.6 mm i.d.）,the mobile phase was 0.02 mol/L sodium dihydrogen phosphate - acetonitrile solution （75：25, V/V）,the detecting wavelength was at 215 nm.The results showed that linear relationship was showed in a concentration rang of 0.1 - 50μg/mL, the linear regression was Y=127.5C＋1.973 （r 〉 0.9999）.Recoveries of levamisole from spiked feed at different concentration were 80% - 110% ,the RSD for intra- and interday data were below 10%.The LOD was 0.2 mg/kg and the LOQ was 0.5 mg/kg in compound feed, the LOD was 0.4 mg/kg and the LOQ was 1 mg/kg in concentrated feed.