液相色谱-质谱法测定饲料中阿维菌素类药物

建立了饲料中阿维菌素类药物(阿维菌素、多拉菌素、埃普菌素和伊维菌素)液相色谱-质谱(LC-MS)检测法. 用乙腈提取样品中的药物, 加水稀释, 加三乙胺调节pH, 经C18固相萃取柱净化, LC-MS法测定. 结果表明, 方法平均回收率为91.3%～99.8%, RSD为2.9%～15% (n=4), 配合饲料、浓缩饲料和预混合饲料中的检出限均为10 μg/kg; 定量限均为20 μg/kg. 方法可用于饲料样品中阿维菌素类药物残留量的确证检测.     

Determination of avermectins in commercial formulations using microemulsion electrokinetic chromatography

Microemulsion electrokinetic chromatography (MEEKC) was developed for quantitative analysis of avermectins, such as abamectin, doramectin and ivermectin, in commercial formulations, using the microemulsion buffer containing a 50 mM phosphate buffer at pH 2.5, 1.1% (v/v) n-octane as oil droplets, 180 mM sodium dodecylsulphate as surfactant, 890 mM 1-butanol as co-surfactant and 30% (v/v) ethanol as organic co-solvent. High accuracy and precision of the method were obtained. The contents of avermectins in commercial formulations determined by MEEKC were found to be insignificantly different with those determined by high performance liquid chromatography (HPLC). Therefore, MEEKC can be used an alternative method to HPLC for quantitative determination of avermectins.