多功能净化柱和固相萃取双重净化-液相色谱质谱法检测青贮饲料中莠去津及其代谢物的残留

Determination of Trace Atrazine and Its Metabolites in Corn Silage by Liquid Chromatography/Mass Spectrometry Using Double Purification with Multifunctional Purifying Column and Solid Phase Extraction

采用多功能净化柱和MCX柱双重为样品的前处理方法,建立了青贮玉米中莠去津及其6种主要代谢产物的高效液相色谱质谱联用分析方法。试样经乙腈水提取,C18色谱柱梯度分离,并以基质匹配曲线外标法定量。结果表明:莠去津及其代谢物在2～100μg/kg范围内线性良好,标准曲线相关系数r均大于0.99。在2～50μg/kg浓度范围内,平均添加回收率在71.01%～113.34%,相对标准偏差为2.58%～15.46%,各目标物检出限(LOD)为1μg/kg,定量检出想(LOQ)为2μg/kg。本方法重现性好,准确度高,能够满足青贮玉米中残留检测的需要。

The purpose of this study was to develop a sensitive LC-MS method for the analysis of atrazine and its metabolites in corn silage. We were able to simultaneously measure atrazine and its major dealkylation and hydroxylation metabolites. An analytical scheme including sample preparation, chromatography and mass spectrometry was developed and optimized. Combined PriboFast TM-C160 with Mix cation-exchange solid-extraction was found to be satisfactory for sample preparation. For qualitative analysis of samples high-performance liquid chromatography/ mass spectrometry methods was used. The method had good precision （relative standard deviations ranging from 2.58%-15.46% at 2, 5, 10 and 50 p,g/kg）, the recoveries ranging from 71.01%-113.34%at 2, 5, 10 and50 μg/kg, limits of detection （LOD） of all analytes was 1 μg/kg. The linear range of our method spanned from 2 to 100 μg/kg with r^2 values of greater than 0. 99. The method was rapid, cost-effective and suitable for corn silage sample analyzed.