超高效液相色谱-三重四极杆-离子阱质谱法检测柑橘中螺虫乙酯及其4种代谢产物

建立了超高效液相色谱-三重四极杆-离子阱质谱定量检测柑橘中螺虫乙酯及其4种代谢产物残留的分析方法。样品以QuEChERS技术为前处理方法进行净化、浓缩，在电喷雾电离（ESI）源、正离子模式下，采用MRM监测模式分析，以基质匹配外标法定量。螺虫乙酯及其4种代谢产物在2~1000 μg/L线性范围内具有良好的线性关系，相关系数（R²）>0.99；方法的检出限（LOD）为0.08~0.49 μg/kg，定量限（LOQ）为0.26~1.62 μg/kg；空白样品添加回收率为94.0%~98.7%，相对标准偏差为1.1%~5.3%。田间试验结果表明，在施药最高推荐量60 mg/kg （有效成分）下，柑橘果肉、果皮、全果样品中螺虫乙酯及其4种代谢产物残留总量分别为5.93~14.20、11.30~17.86和1.30~16.51 μg/kg，残留量均低于国家标准最大残留限量值1.00 mg/kg。该方法操作简便，快速准确，灵敏度高，分离效果好，能够有效降低基质干扰效应，准确度与精密度均能达到定量分析要求，适用于柑橘中螺虫乙酯及其代谢产物残留的定性定量检测。

Determination of spirotetramat and its four metabolites in citrus by ultra-high performance liquid chromatography-triple quadrupole-ion trap mass spectrometry

A method for the simultaneous determination of spirotetramat and its four metabolites in citrus was developed by ultra-high performance liquid chromatography-triple quadrupole-ion trap mass spectrometry (UPLC-Q TRAP MS).The samples were extracted with acetonitrile and purified by QuEChERS pretreatment.The extracts were detected using an electrospray ionization (ESI) positive ion source under multiple reaction monitoring (MRM) mode, and quantified by matrix matching external standard method.The results showed that spirotetramat and its four metabolites had good linearities in the range of 2-1000 μg/L with correlation coefficients (R²) greater than 0.99.The limits of detection (LODs) of spirotetramat and its four metabolites were in the range of 0.08 to 0.49 μg/kg, while the limits of quantification (LOQ) were in the range of 0.26 to 1.62 μg/kg.The average spiked recoveries were in the range of 94.0% to 98.70%, and the relative standard deviations were 1.1%-5.3%.The results from field trials showed that the contents of the final residues of spirotetramat and its four metabolites in the flesh, peel and whole fruit samples were 5.93-14.20, 11.30-17.86 and 1.30-16.51 μg/kg with the highest recommended dose of 60 mg/kg (active ingredient).The residues in harvested citrus were lower than the national standard maximum residue limit (1.00 mg/kg).The method is simple, rapid and accurate, with a high sensitivity and good separation effect, and the effect of matrix interference can be effectively reduced.The accuracy and precision of this method can meet the requirements of quantitative analysis.The method is suitable for the qualitative and quantitative detection of spirotetramat and its four metabolites in citrus.