QuEChERS-UPLC-MS/MS法同时测定刺梨中11 种农药残留

目的：建立高维生素含量刺梨果实中11 种常用农药残留量的测定方法。方法：采用添加回收实验筛选和优化QuEChERS前处理方法的提取剂和净化方式，最终选用乙腈提取，N-丙基乙二胺和石墨化碳黑进行净化，以0.1%甲酸溶液和乙腈为流动相，用0.4 mL/min的流速梯度洗脱；在电喷雾正离子模式下，通过优化各农药离子对的碎裂电压、碰撞能量，以获得最佳响应，采用基质加标准曲线进行定量。结果：经方法验证，11 种农药的方法检出限在1.31～8.56 μg/kg之间，定量限在4.13～43.57 μg/kg之间，线性相关系数（R）在0.991 2～0.999 9之间；方法选择3 个添加水平进行添加回收率实验，回收率在84.5%～103.8%之间，相对标准偏差（n=6）在1.2%～8.5%之间。结论：该方法前处理快速、灵敏、准确，可为刺梨中农药的监管提供技术支持。

Simultaneous Determination of 11 Pesticides in Rosa roxburghii by QuEChERS-Ultra-high Performance Liquid Chromatography-Tandem Mass Spectrometry

Objective: A method for the determination of 11 common pesticides in Rosa roxburghii Tratt. was established using QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction and ultra-high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods: The QuEChERS conditions were optimized by performing spiked recovery tests. Acetonitrile was used for extraction, and primary secondary amine (PSA) and graphitized carbon black (GCB) were used for purification. The chromatographic separation was achieved using gradient elution with a mobile phase consisting of 0.1% formic acid water and acetonitrile at a flow rate of 0.4 mL/min. In the positive ion mode using an electrospray ionization source, the fragmentor voltage, collision energy and ion pairs for each pesticide were optimized to obtain the best response, and the pesticides were quantified by matrix-matched calibration. Results: The limits of detection (LODs) for all pesticides were in the range of 1.31–8.56 μg/kg, and the limits of quantitation (LOQs) ranged from 4.13–43.57 μg/kg. The correlation coefficients (R) of the calibration curves were in the range of 0.991 2–0.999 9. The average recoveries at three spiked levels ranged from 84.5% to 103.8% (n = 6) with relative standard deviations (RSDs) of 1.2%–8.5%. Conclusion: This method was rapid, sensitive and precise, and could provide technical support for the determination of pesticide residues in R. roxburghii.