气相色谱-负化学离子源质谱法检测食品中苯醚甲环唑的残留量

Determination of Difenoconazole Residue in Foods by Gas Chromatography-Negative Chemical Ionization Mass Spectrometry

建立了一种用于各种食品中苯醚甲环唑残留量的气相色谱-负化学离子源质谱（GC—MS／NCI）检测方法。用乙酸乙酯对各类样品中的苯醚甲环唑进行提取，固相萃取（SPE）净化后由GC—MS／NCI在选择离子监测模式下进行测定。方法的准确度和精密度高，多数样品在0．01，0．04，0．10mg／kg三个添加水平下苯醚甲环唑的回收率处于70％和120％之间，相对标准偏差（RSD）不大于9．5％。方法在0．02～1．00mg／L范围内有良好的线性关系，且灵敏度高，最低检测限达到0．0005mg／kg；选择性好，抗干扰能力强，能消除复杂基质带来的干扰，适合各种食品中苯醚甲环唑残留量的确证分析。

A method is presented for the determination of dffenoconazole residue in all kinds of foods by solid phase extraction-gas chromatography-negative chemical ionization mass spectrometry （SPE-GC-MS/NCI）. Difenoconazole residue was extracted with ethyl acetate from different samples, such as perilla leaves, carrots, spinach powder, rice, gram, jasmine flower tea, oolong tea, strawberries, sauce, bee honey, beef, chicken and eels, etc. The extracts were cleaned-up by active carbon SPE column connected to alumina neutral SPE column or Florisil SPE column only. Analytical screening was determined by the technique of GC-MS/NCI on selected ion monitoring mode. The recoveries of dffenoconazole in most samples were in the range from 70% to 120% at three spiked levels, 0.01 mg/kg, 0.04 mg/kg and 0. 10 mg/kg, and the relative standard deviations （RSDs） were below 9.5%. The linearity of the method is good from 0.02 to 1.00 mg/L, and limit of detection （ LOD ） was 0.000 5 or 0. 001 0 mg/kg for different type samples. The method is selective without interference and is suitable for determination and conformation of difenoconazole residue in all kinds of foods.