Public Health Research Center of Valencia (CSISP), Food Safety Area, Av. Cataluña, 21, 46020 Valencia, Spain.
Anal Bioanal Chem. 2011 May;400(5):1315-28. doi: 10.1007/s00216-011-4656-5. Epub 2011 Jan 28.
A rapid and easy method has been proposed, optimized and evaluated for quantitative determination at trace level of a representative group of non-polar pesticides in fat samples. The method includes n-hexane-saturated acetonitrile extraction, fat precipitation by cooling pre clean-up followed by dispersive solid-phase extraction (d-SPE) based on QuEChERS procedure clean-up. Determination was performed by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. Efficiency of the d-SPE clean-up step was evaluated by comparison with fat oxidation treatment and gel permeation chromatography. Different combinations of d-SPE extraction reagents and sample amounts were tested in order to minimize matrix co-extractives and interferences. Best recoveries were obtained with 1200 mg of MgSO(4), 400 mg of end-capped C(18), 400 mg of PSA and 1 g of sample amount. SIM method, matrix effect, precision, and accuracy were evaluated with spiked pork fat samples for 38 representative pesticides. Results of this study showed that this technique is applicable in routine analysis for its application into monitoring programs. It simplifies time-consuming clean-up steps and allows a satisfactory long-term chromatographic performance.
一种快速、简便的方法已被提出、优化和评估，用于在脂肪样品中痕量水平定量测定一组有代表性的非极性农药。该方法包括用正己烷饱和的乙腈提取，冷却预净化后用 QuEChERS 程序净化进行脂肪沉淀，然后用分散固相萃取（d-SPE）进行净化。通过气相色谱-质谱（GC-MS）在选择离子监测（SIM）模式下进行测定。通过与脂肪氧化处理和凝胶渗透色谱的比较，评估了 d-SPE 净化步骤的效率。为了最小化基质共提取物和干扰，测试了不同的 d-SPE 萃取试剂和样品量的组合。用 1200mg 的 MgSO(4)、400mg 的端封 C(18)、400mg 的 PSA 和 1g 的样品量，获得了最佳的回收率。用添加了 38 种代表性农药的猪肉脂肪样品对 SIM 方法、基质效应、精密度和准确性进行了评估。研究结果表明，该技术适用于监测计划中的常规分析。它简化了耗时的净化步骤，并允许令人满意的长期色谱性能。
