气相色谱-串联质谱测定水稻中10种拟除虫菊酯类杀虫剂农药残留

目的]建立水稻中10种拟除虫菊酯类杀虫剂农药残留气相色谱-串联质谱测定方法。方法]将样品用乙腈提取,采用无水硫酸镁、氯化钠盐析,弗罗里硅土柱萃取净化进行前处理,采用多反应监测模式测定。结果]浓度为0.010~0.500 mg/L范围内与峰面积呈线性关系,相关系数均大于0.99,最低检测限在0.005~0.010 mg/kg。当添加水平为0.05、0.10、0.20 mg/kg时(n=5),回收率为75.0%~115.5%,相对标准偏差为3.9%~6.9%。结论]该方法简便、准确、可靠,能同时定性和定量,可用于水稻中拟除虫菊酯类杀虫剂农药残留的快速检测与确证。

Determination of 10 Pyrethroids Pesticide Residues in Rice by GC-MS-MS

Objective] A method was developed for the determination of 10 pyrethroids pesticide residues in rice by GC-MS-MS.Method] Pyrethroids were extracted with acetonitrile, followed by a salting-out step with anhydrous magnesium sulfate and sodium chloride, cleaned up by florisil solid phase extraction (SPE) cartridge, and determined by multiple reaction monitoring mode.Result] The method showed good linearity over the range of 0.010-0.500 mg/L for 10 pyrethroids pesticide with correlation coefficients over 0.99.The detection limits were 0.005-0.010 mg/kg.The method was validated by analyzing samples spiked with 0.05, 0.10, 0.20 mg/kg of 10 pyrethroids pesticide, respectively.The average recoveries in rice ranged from 75.0%-115.5%, and the relative standard deviations (RSD)were between 3.9%-6.9%.Conclusion]The method is easy, accuracy and reliable, which can meet the requirement for the simultaneous determination and confirmation of pyrethroids pesticide residues in rice.