QuEChERS-超高效液相色谱-串联质谱法测定蔬菜中9种甲氧基丙烯酸酯类杀菌剂

建立了采用QuEChERS方法提取净化，超高效液相色谱-串联质谱法（UPLC/MS/MS）同时测定蔬菜中的9种甲氧基丙烯酸酯（Z-苯氧菌酯、E-苯氧菌酯、嘧菌酯、肟嘧菌胺、醚菌胺、啶氧菌酯、吡唑醚菌酯、肟菌酯、嘧螨酯）杀菌剂残留量的方法。样品经乙腈提取，采用正交试验验优选N-丙基乙二胺（PSA）和C₁₈以及石墨化炭黑（GCB）净化用量。使用0.05%甲酸水和0.05%甲酸乙腈作为流动相梯度洗脱，目标化合物经岛津Shim-PackC₁₈色谱柱（2.1 mm×50 mm，2 μm）分离，在正离子模式下进行测定。结果表明，9种甲氧基丙烯酸酯类杀菌剂在1～100 ng/mL范围内线性关系良好，决定系数在0.9942～0.9995之间，方法检出限（LOD）为0.05～0.3 μg/kg，定量限（LOQ）为0.2～0.9 μg/kg。在2、10和20 μg/kg三个添加水平下，五种蔬菜的回收率在77.26%～111.73%之间，相对标准偏差在0.46%～6.59%之间。该方法准确、快速、便捷、灵敏度高，能够满足蔬菜中9种甲氧基丙烯酸酯类杀菌剂的痕量检测要求。

Determination of 9 Strobilurin Fungicides in Vegetables by QuECHERS-Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

The method was established for the nine strobilurin fungicides in vegetables by using QuEChERS method.The samples were extracted with acetonitrile and purified with n-propyl-ethylenediamine(PSA),C18 and graphitized carbon black(GCB)by orthogonal test.Using 0.05%formic acid water and 0.05%formic acid acetonitrile as mobile phase gradient elution,the target compounds were separated by Shimadzu shim pack C18 column(2.1 mm×50 mm,2μm)and determined in positive ion mode.The linear relationship of 9 strobilurin fungicides was good in the range of 1~100 ng/mL,the coefficient of determination was between 0.9942~0.9995.The LOD was 0.05~0.3μg/kg and the LOQ was 0.2~0.9μg/kg.At the levels of 2,10 and 20μg/kg,the recovery rates of the five vegetables were 77.26%~111.73%,and the relative standard deviation was 0.46%~6.59%.The method is accurate,rapid,convenient and sensitive,which can meet the requirements of trace detection of nine strobilurin fungicides in vegetables.