National Referral Laboratory, ICAR-National Research Centre for Grapes, Pune, Maharashtra, India.
National Referral Laboratory, ICAR-National Research Centre for Grapes, Pune, Maharashtra, India.
Chemosphere. 2017 Oct;184:1036-1042. doi: 10.1016/j.chemosphere.2017.06.086. Epub 2017 Jun 20.
A buffered ethyl acetate extraction method was optimized and validated in raisin matrix to monitor 276 pesticides by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The final method involved homogenization of raisinsalong with water 1:1 raisins: water followed by extraction using ethyl acetate (10 mL/10 g raisins homogenate in presence of 0.1 mL acetic acid, 0.5 g sodium acetate and 10 g sodium sulfate, and cleanup by dispersive solid phase extraction with primary secondary amine sorbent (25 mg/5 mL extract). 276 pesticides were estimated within 20 min of chromatographic run time by retention time dependent 'scheduled multiple reaction monitoring' (sMRM) by LC-MS/MS.The method was validated as per European guideline, DG-SANTE/11945/2015, at 2, 10, and 25 ng/g spiking levels where the method precision in terms of repeatability was <15% at 10 ng/g for 93.8% of the compounds. The Limit of quantification (LOQ) ranged between 0.01 and 10 ng/g with recoveries 70-120% with ≤20% RSD for 93.5% of compounds at regulatory default MRL of 10 ng/g. The matrix induced signal suppressions or enhancement were moderate (60-130% accuracy against solvent standard) for 85% compounds in white raisins and 67% compounds in black raisins. The method was successfully applied for screening of 94 market samples of raisins for the target analytes. The dietaryexposures calculated against the average concentrations detected were wellbelow the maximum permissible intake (MPI) values and the collected raisin samples were considered safe for human consumption without any acute toxicity hazard.
一种缓冲乙酸乙酯提取方法在葡萄干基质中得到了优化和验证，用于通过液相色谱-串联质谱法（LC-MS/MS）分析监测 276 种农药。最终方法包括将葡萄干与水 1:1 混合均匀，然后用乙酸乙酯（10 mL/10 g 葡萄干匀浆中加入 0.1 mL 乙酸、0.5 g 醋酸钠和 10 g 硫酸钠）提取，并通过分散固相萃取用一级二级胺吸附剂（25 mg/5 mL 提取物）进行净化。通过 LC-MS/MS 的保留时间相关“预定多重反应监测”（sMRM），在 20 分钟的色谱运行时间内可以估算 276 种农药。该方法按照欧洲指南 DG-SANTE/11945/2015 进行了验证，在 2、10 和 25 ng/g 加标水平下，该方法的精密度以重复性表示，在 10 ng/g 时 93.8%的化合物的重复性小于 15%。定量限（LOQ）范围在 0.01 和 10 ng/g 之间，回收率为 70-120%，RSD 小于 20%，对于 93.5%的化合物，在法规默认的 10 ng/g 的 MRL 下。基质诱导的信号抑制或增强为中等（相对于溶剂标准的 60-130%的准确度），在白葡萄干中有 85%的化合物和黑葡萄干中有 67%的化合物。该方法成功应用于 94 个市场葡萄干样品中目标分析物的筛选。根据检测到的平均浓度计算的膳食暴露量远低于最大允许摄入量（MPI）值，所采集的葡萄干样品被认为对人类食用是安全的，没有任何急性毒性危害。
