烹饪方法对鸡蛋及鸡肉中氟虫腈及其代谢物残留量的影响

建立鸡蛋及鸡肉中氟虫腈及其代谢物氟甲腈、氟虫腈砜、氟虫腈亚砜的超高效液相色谱-串联质谱定量检 测方法。采用乙腈沉淀蛋白，并用QuEChERS处理样本后进样分析。结果表明，4 种目标化合物的平均加标回收率 在75.7%～104.5%之间，相对标准偏差在1.3%～10.4%之间。利用此方法对高、低2 个浓度的被污染样本烹调前后的 氟虫腈及其代谢物含量进行检测。分别采用蒸锅中蒸制10 min、平底锅中小火煎制5 min及沸水中煮制10 min的烹调 方法对鸡蛋和鸡肉阳性样本进行烹调，氟虫腈砜的含量在鸡蛋和鸡肉烹调前后没有发生较大变化，在氟虫腈砜含量 变化最大的煎制法处理之后，鸡蛋中的氟虫腈砜含量也只降低了12.2%和16.2%，鸡肉中只降低了7.3%和14.7%。结 果表明，烹调并不会使鸡蛋和鸡肉中氟虫腈及其代谢物的含量发生明显变化，加强源头管控是最有效的监管方法。

Effects of Cooking Methods on Fipronil and Its Metabolites Residues in Eggs and Chicken

A quantitative method for the determination of fipronil and its metabolite, flupronex sulfoxide and fipronil sulfoxide, in eggs and chicken was established by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS). The protein in samples was precipitated with acetonitrile prior to QuEChERS extraction. The extract was analyzed by UPLC-MS-MS. The average recoveries of the 4 compounds from spiked samples were between 75.7% and 104.5%, with relative standard deviations (RSD) of 1.3% to 10.4%. The method was used to detect the contaminated samples at two different concentrations before and after cooking. The content of fluonitrile sulfoxide in the positive samples did not change greatly before and after cooking for 10 min in steaming pot, 5 min in flat bottomed pan at medium-to-small fire or 10 min in boiling water. Although the maximum change was observed in fluonitrile sulfoxide after frying, it was reduced only by 12.2% and 16.2% in the eggs and by 7.3% and 14.7% in the chicken. The results of this study showed that cooking does not changes in the contents of fipronil and its metabolites in eggs and chicken. Strengthening the control of contamination sources is the most effective method for supervision.