Abstract The aim of this study is to determine optimum extraction and clean up conditions for different pesticide residues in milk and dairy products by using GC–MS. A Box-Behnken design with 3-level 4-variable followed by Plackett-Burman screening design was employed in order to optimize significant variables of the modified QuEChERS method. After the determination of optimal experimental conditions, the proposed method was validated according to SANCO guideline. The method presented recoveries between 72.5% and 120.0% for 25 pesticides, which is satisfactory when one considers the performance criteria detailed in this guideline. The repeatability and within-laboratory reproducibility ranged from 0.95 to 14.62% and from 1.45 to 17.94%, respectively. Also, the method allowed the determination at low detection limits within short analysis time (

中文翻译：

---

通过 GC-MS 测定牛奶和乳制品中农药多残留的实验设计优化改进的 QuEChERS 方法

摘要 本研究的目的是使用 GC-MS 确定牛奶和乳制品中不同农药残留的最佳提取和净化条件。采用 3 水平 4 变量的 Box-Behnken 设计，然后是 Plackett-Burman 筛选设计，以优化改进的 QuEChERS 方法的重要变量。在确定最佳实验条件后，根据 SANCO 指南对所提出的方法进行了验证。该方法对 25 种农药的回收率为 72.5% 至 120.0%，考虑到本指南中详述的性能标准，这是令人满意的。重复性和实验室内再现性的范围分别为 0.95 至 14.62% 和 1.45 至 17.94%。此外，该方法允许在较短的分析时间内以低检测限进行测定（