QuEChERS-高效液相色谱-串联质谱法检测茶叶中二硫代氨基甲酸酯(盐)残留量

Determination of Dithiocarbamate(Salt) Residues in Tea by QuEChERS-High Performance Liquid Chromatography-Tandem Mass Spectrometry

文章建立了分散固相萃取技术(Dispersive solid-phase extraction,QuEChERS)结合高效液相色谱-串联质谱法(High performance liquid chromatography-tandem mass spectrometry,HPLCMS/MS)检测茶叶中二硫代氨基甲酸酯(盐)类杀菌剂(Dithiocarbamate(salt),DTCs)中2种亚型(代森锰锌和甲代森锌)残留量的方法。将茶叶样品经碘甲烷甲基化衍生,酸化的乙腈溶液提取,用QuEChERS法净化,Symmetry C_(18)色谱柱分离,HPLC-MS/MS外标法定量。结果表明,代森锰锌和甲代森锌检出限为2.5μg/kg,定量限为5μg/kg;在2.5~50.0μg/kg浓度范围内线性关系良好(r>0.99),平均回收率为86.09%~104.97%,相对标准偏差为1.73%~10.89%。综上所述,该方法精密度和准确度较好,操作简单,提高了检测效率。

In this paper, a method for the determination of the residues of two subtypes(mancozeb and propineb) of dithiocarbamate(salt) in tea was established. The method combines with dispersive solid-phase extraction(QuEChERS) and high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS). In this study, tea samples were derivatized by methyl iodide, extracted with acidified acetonitrile solution, purified by QuEChERS method, separated by Symmetry C_(18)column, and quantified by HPLC-MS/MS external standard method. The result showed the detection limit of mancozeb and propineb were 2.5 μg/kg, the limit of quantification were 5 μg/kg;the linear relationship was good in the concentration range of 2.5~50.0 μg/kg(r>0.99), and the average recoveries were 86.09% to 104.97%,and the relative standard deviations ranged from 1.73% to 10.89%. In summary, The method has good precision and accuracy, simple operation and improved detection efficiency.