QuEChERS-气相色谱-三重四极杆串联质谱法测定青贮玉米中20种农药残留

Determination of 20 pesticide residues in silage corn by QuEChERS gas chromatography triple quadrupole mass spectrometry

试验旨在建立改良的QuEChERS技术,结合气相色谱-三重四极杆串联质谱法测定青贮玉米中20种农药残留。结果显示,通过优化前处理QuEChERS条件,选取乙腈-丙酮(1∶1)为农药残留提取溶剂,WondaPak QuEChERS净化管Ⅲ为净化剂,所测20种农药残留的加标回收率为75.98%~99.02%,相对标准偏差为0.12%~11.65%。在0.05~1.00 mg/L的浓度范围内,所测20种农药的线性关系良好,相关系数(r)≥0.996 7,方法检出限为0.032~0.453μg/kg,方法定量限为0.107~1.51μg/kg。研究表明,采用改良的QuEChERS技术,结合气相色谱-三重四极杆串联质谱法检测青贮玉米中的农药残留,具有前处理便捷、重复性好、灵敏度高等优势,为青贮玉米中农药残留分析提供参考。

The experiment was to establish an improved QuEChERS technology,combined with gas chromatography triple quadrupole mass spectrometry to determinate 20 pesticide residues in silage corn.The results showed that by optimizing pre-treatment conditions of QuEChERS,acetonitrile acetone(1∶ 1) was selected as solvent for pesticide residue extraction,and WondaPak QuEChERS purification tube Ⅲ was used as purification agent.The recovery rates of 20 pesticide residues measured were 75.98%~99.02%,with a relative standard deviation of 0.12%~11.65%.In the concentration range of 0.05~1.00 mg/L,the linear relationship was good,and r ≥ 0.996 7.The detection limits were 0.032~0.453 μg/kg,and the quantitation limits were 0.107~1.51 μg/kg.The experiment indicates that using improved QuEChERS technology combined with gas chromatography-triple quadrupole mass spectrometry to detect pesticide residues in silage corn has advantages of convenient pre-treatment,good repeatability,and high sensitivity,to provide reference for analysis of pesticide residues in silage corn.