A fast method based on Fe₃O₄ magnetic nanoparticles (Fe₃O₄ MNPs) modified QuEChERS integrated to dispersive liquid-liquid microextraction (DLLME) coupled with gas chromatography-mass spectrometry was established for the determination of 8 organochlorine pesticides (OCPs) in green leafy vegetables. The factors involved in the purification by QuEChERS and concentration by DLLME were optimized. In the QuEChERS process, Fe₃O₄ MNPs were used as a new impurity adsorbent after the sample extraction procedure by acetonitrile, which achieved phase separation rapidly. Carbon black was used as an alternative to costly graphitized carbon black without affecting the recovery. In the process of DLLME, 1 mL of the extract obtained by QuEChERS was used as the dispersive solvent, 40 μL of chloroform was used as the extractive solvent, and 4 mL of water was added. Making them mix well, then the dispersed liquid-liquid microextraction concentration was subsequently carried out. The enrichment factors of 8 OCPs ranged from 22.8 to 36.6. The recoveries of the proposed method ranged from 78.6% to 107.7%, and the relative standard deviations were not more than 7.5%. The limits of detection and limits of quantification were 0.15–0.32 μg/kg and 0.45–0.96 μg/kg, respectively. The method has been successfully applied to the determination of OCPs in green leafy vegetable samples.

中文翻译：

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Fe3O4磁性纳米粒子修饰的QuEChERS结合分散液微萃取-气相色谱-质谱法测定绿色蔬菜样品中的有机氯农药

建立了一种基于Fe ₃ O ₄磁性纳米颗粒（Fe ₃ O ₄ MNPs）修饰的QuEChERS的快速液相色谱-质谱联用的快速测定方法，该方法用于测定8种有机氯农药（OCP）。绿叶蔬菜。优化了通过QuEChERS纯化和通过DLLME浓缩所涉及的因素。在QuEChERS过程中，Fe ₃ O ₄用乙腈萃取样品后，MNPs被用作新的杂质吸附剂，可快速实现相分离。炭黑被用作昂贵的石墨化炭黑的替代品，而不会影响回收率。在DLLME的过程中，1毫升通过的QuEChERS得到的提取物用作分散溶剂，40  μ氯仿L的用作萃取溶剂，加入4mL水。使它们充分混合，然后进行分散的液-液微萃取浓缩。8种OCP的富集系数范围为22.8至36.6。该方法的回收率在78.6％至107.7％之间，相对标准偏差不超过7.5％。检测和定量的限制的限为0.15-0.32  μ克/千克和0.45-0.96  μ，克/千克分别。该方法已成功应用于绿叶蔬菜样品中OCP的测定。