QuEChERS-高效液相色谱串联质谱法测定牛奶中6种玉米赤霉醇类激素药物残留量

Determination of Six Zeranols in Milk by QuEChERS-High Performance Liquid Chromatography- Tandem Mass Spectrometry(HPLC-MS/MS)

建立了高效液相色谱串联质谱法（HPLC-MS/MS）测定牛奶中的玉米赤霉醇类激素药物残留量的方法。样品用乙酸乙酯提取,经QuEChERS法快速净化,采用HPLC-MS/MS在负电喷雾多反应监测模式下检测。6种玉米赤霉醇类激素药物在1.0~100.0μg/L含量范围内线性关系良好,相关系数均高于0.999,方法定量限为0.33~1.00μg/kg;在2.0μg/kg、5.0μg/kg、10.0μg/kg三个浓度水平下样品加标回收率的范围为83.2%~111%,相对标准偏差为0.13%~2.2%（n=6）。该方法操作简单、快速、准确,适用于牛奶中6种玉米赤霉醇类激素药物残留量的测定。

A method of determining six zeranols in milk by High Performance Liquid Chromatography-tandem mass spectrometry（HPLC-MS/MS）was established. The residues in the samples were extracted by ethyl acetate, cleaned up by developed Qu ECh ERS method, and then analyzed by using HPLC-MS/MS in multiple reaction monitoring（MRM） mode via negative electrospray ionization. External standard method was used to determine the residue contents with a good linear relationship（1.0~100.0 μg/L, r20.999）. The limits of quantification（LOQ）were 0.33~1.00 μg/kg. The recoveries of zeranols at three levels of 2.0 μg/kg, 5.0 μg/kg, and 10.0 μg/kg were from 83.2 % to 111 % with the relative standard deviations（RSDs）of 0.13 %~2.2 %（n=6）in milk. The method is simple, rapid and characterized with acceptable sensitivity and accuracy to meet the requirements of the zeranols analysis.This developed procedure is suitable for the determination of zeranols in milk.