超高效液相色谱-串联质谱法测定果蔬中氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯残留量

摘要

建立超高效液相色谱-串联质谱同时测定蔬菜和水果中氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯残留量的分析方法.样品经乙腈均质提取,混合使用乙二胺-N-丙基硅烷和十八烷基硅烷基质分散净化剂净化,以C18色谱柱分离待测物,采用电喷雾离子化,正离子扫描和动态多反应监测模式检测,基质匹配标准溶液外标法定量.氟啶虫胺腈在0.2~100 μg/L之间,Pyrifluquinazon在0.02~10 μg/L之间,螺虫乙酯在0.1~10 μg/L之间的范围内线性关系良好,相关系数均大于0.9990.在4个添加水平进行氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯添加回收率实验,平均添加回收率在79.9%~103.9%之间,相对标准偏差在3.3%~8.8%之间.氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯的方法定量限分别为0.334、0.0405 μg/kg和0.378 μg/kg,检出限分别为0.100、0.0122 μg/kg和0.133 μg/kg.该方法快速简便、定量准确,可满足多种蔬菜和水果中氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯3 种杀虫剂的残留检测要求.%In this study, a rapid, highly sensitive and selective method was developed for the simultaneous determination of residues of sulfoxaflor, pyrifluquinazon and spirotetramat in fruits (apple, grape, and strawberry) and vegetables (cucumber, onion, Chinese cabbage, spinach, and welsh onion) by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The target compounds were extracted from the samples with acetonitrile and cleaned up with dispersive solid phase extraction using primary secondary amine (PSA) and C18as solid phase before being separated on a C18 column. Two pairs of precursor product ion transitions for sulfoxaflor, pyrifluquinazon and spirotetramat were measured and evaluated under the positive multiple reaction monitoring (MRM) mode. Matrix effects were tested by comparison of reference standards in pure solvent with matrix-matched standards of each matrix. In order to reduce the systematic error, quantification was performed using matrix-matched standard calibration curves. Satisfactory linearity in the concentration range of 0.2-100, 0.02-10 and 0.1-10 μg/L for sulfoxaflor, pyrifluquinazon and spirotetramat, respectively were obtained with correlation coefficients (r) of higher than 0.999 0. Average recoveries of sulfoxaflor, pyrifluquinazon and spirotetramat added to cucumber, grape, apple and scallion ranged from 79.9% to 103.9%, with relative standard deviations (RSD) from 3.3% to 8.8%. The limits of quantification (LOQs) were 0.334, 0.040 5 and 0.378 μg/kg, and the limits of detection (LODs) were 0.100, 0.012 2 and 0.133 μg/kg for sulfoxaflor, pyrifluquinazon and spirotetramat respectively. The method is quick, easy, effective, sensitive and accurate, and can meet the requirements for the determination of residues of sulfoxaflor, pyrifluquinazon and spirotetramat in fruits and vegetables.