蔬菜中11种苯甲酰脲类农药残留的液相色谱-串联质谱法测定

Determination of 11 Benzoylurea Insecticides Residues in Vegetable by LC-MS/MS

建立了同时测定蔬菜中氯呲苯脲、除虫脲、灭幼脲、杀铃脲、氟铃脲、氟丙氧脲、氟苯脲、氟啶蜱脲、氟虫脲、丁醚脲、氟啶脲11种苯甲酰脲类农药残留的液相色谱-串联质谱分析方法。试样经乙腈提取，N-丙基乙二胺（PSA）和C18填料分散崮相萃取净化，C18柱反相液相色谱分离，以甲醇-0．005 moLCL醋酸铵溶液为流动相梯度洗脱，电喷雾负离子模式离子化，多反应监测方式监测，三重四极杆质谱测定。结果表明：试样中添加10、20、50μg/kg的11种苯甲酰脲类农药，回收率为69％～109％，相对标准偏差小于16％（n=5）。该方法操作简便、稳定性好、灵敏度高，检出限（LOD）为3μg／kg，定量下限（LOQ）为10μg/kg.

A LC -MS/MS method was developed for the simultaneously determination of 11 benzoylurea insecticides residues, including forehlorfenuron, diflubenzuron, chlorbenzuron, triflumuron, hexaflumuron, lufenurou, teflubenzuron, fluazuron, flufenoxuron, diafenthiuron, ehlorfluazuron, in vegetable samples. The sample was extracted with acetonitrile and cleaned up on column filled with PSA and C18. The 11 benzoylurea insecticides residues were separated on C18, column with gradient elution employing methane（A） -5 mmol/L ammonium acetate （B） as mobile phase, and detected with negative-ion electrospray ionisation - mass spectrometry （ ESI - MS） under multiple reaction monitoring（MRM） mode. The calibration curves were linear over the concentration in the range of 3-200 μg/kg for 11 benzoylureas. The recoveries of benzoylureas in vegetable sample at three spiked concentration levels of 10, 20 and 50 μg/kg ranged from 69 % to 109 % with relative standard deviations（RSDs） less than 16% （n = 5）. The limits of quantitation（LOQs） of benzoylurea insecticides were 10 μg/kg, and limits of deteetion（LODs） were 3 μg/kg. The method is simple, rapid, accurate, and could be applied in the determination of multi-class benzoylurea insecticides in broccoli and kidney beans samples.