液相色谱-串联质谱法测定植物源性产品中5个酰胺类杀菌剂残留

目的：建立液相色谱-串联质谱法测定植物源性产品中5个酰胺类杀菌剂（双炔酰菌胺、噻唑菌胺、吲唑磺菌胺、硅噻菌胺、吡噻菌胺）的含量。方法：样品用1%甲酸乙腈溶液进行提取，经无水硫酸镁、N-丙基乙二胺（PSA）、石墨化炭黑（GCB）分散萃取净化，采用Accucore XL C₁₈色谱柱（4.6 mm×150 mm，4.0 μm）分离，以甲醇（A）和0.1%甲酸水溶液（B）为流动相进行梯度洗脱（0~1.0 min，45% A；1.0~3.0 min，45% A→80% A；3.0~8.0 min，80% A→95% A；8.0~12.0 min，95% A；12.0~13.0 min，95% A→45% A；13.0~17.0 min，45% A），流速为0.4 mL·min^-1。质谱采用多反应监测正离子扫描模式，基质匹配标准曲线定量。结果：测定结果显示，在草莓、白菜等水果蔬菜中未检测到酰胺类杀菌剂；在葡萄中有检出酰胺类杀菌剂，检测结果均符合欧盟等法规要求。5个酰胺类杀菌剂标准曲线线性良好，相关系数在0.993 7~0.999 6。5个酰胺类杀菌剂检出下限为3.0 μg·kg^-1，定量下限为10.0 μg·kg^-1。对6种植物源性产品进行10.0、20.0和100.0 μg·kg^-1 3个水平加标回收试验，平均回收率范围为76.3%~117.1%，RSD为0.70%~14.3%。结论：该方法能满足国内外标准法规对植物源性产品中5个酰胺类杀菌剂残留限量的检测要求。

objective: To develop a method for simultaneously determination of 5 amide fungicides (mandipropamid;ethaboxam;amisulborum;silthiopham;penthiopyrad)in plant-derived product using liquid chromatography-tandem mass spectrometry. Methods: Sample was extracted with 1% formic acid in acetonitrile and purified by Querchers method with magnesium sulfate, PSA, GCB. The Accucore XL C₁₈ column (4.6 mm×150 mm, 4.0 μm)was adopted with the mobile phase consisting of methonal (A)-0.1% formic acid solution (B)with gradient elution (0-1.0 min, 45%A, 55%B;1.0-3.0 min, 45%A→80%A, 55%B→20%B;3.0-8.0 min, 80%A→95%A, 20%B→5%B;8.0-12.0 min, 95%A, 5%B;12.0-13.0 min, 95%A→45%A, 5%B→55%B;13.0-17.0 min, 45%A, 55%B)at a flow rate of 0.4 mL·min^-1. Mass spectrometer was operated in the positive ion mode using select reaction monitoring. Matrix-matched calibration curve was used for quantitative analysis. Results: Five amide fungicides were not detected in strawberry and cabbage. Amide fungicides were detected in grape. The results of the test meet the requirements of the European Union regulations. The linearity of the calibration curve was from 2.0 to 60.0 ng·mL^-1 with correlation coefficient of 0.993 7-0.999 6. The limit of detection in the method was 3.0 μg·kg^-1. The average recovery of amide fungicides at three levels of 10.0, 20.0 and 100.0 μg·kg^-1 were in the range of 76.3%-117.1% with the RSDs of 0.7%-14.3%. Conclusion: This method complied with domestic and foreign laws and regulations for five amide fungicides in plant-derived product.