气相色谱-串联质谱法同时测定鲫鱼及产地底泥中41种清塘常用农药残留

Determination of 41 pond cleaning commonly used pesticide residues in crucian carp and bottom sediment by gas chromatography-tandem mass spectrometry

采用改良QuEChERS前处理方法,结合气相色谱-串联质谱(GC-MS/MS)仪,建立了鲫鱼和产地底泥中41种农药残留的检测方法。鲫鱼样品用V(乙腈):V(乙酸乙酯)=1:1提取,经600 mg碱性氧化铝净化;产地底泥样品用乙酸乙酯提取,经600 mg弗罗里硅土和150 mg石墨化碳黑净化。用GC-MS/MS分析,采用HP-5MS柱进行分离,电子轰击离子源(EI)动态多反应监测模式(dMRM)检测,以空白基质匹配标准溶液外标法绘制标准曲线,进行定量。结果表明:1)鲫鱼中41种农药的仪器检出限(LOD)在0.05~2.5μg/L之间,方法定量限(LOQ)在0.1~5.0μg/kg之间,线性相关系数(r)在0.9960~0.9999之间;在LOQ、2 LOQ和10 LOQ 3个添加水平下,41种农药在鲫鱼中的平均回收率在73%~116%之间,相对标准偏差(RSD)在0.65%~13%之间(n=6)。2)养殖底泥中41种农药的仪器LOD在0.05~2.5μg/L之间,方法L OQ在0.1~5.0μg/k g之间,r在0.9964~1.000之间;在L O Q、2 L O Q和10 LOQ 3个添加水平下,41种农药在底泥中的平均回收率在73%~104%之间,RSD在0.051%~10%之间(n=6)。该方法前处理快速,检测方法灵敏、准确,在鲫鱼和底泥中检测酰胺类、三嗪类、苯基吡唑类、有机氯和有机磷等农药多残留具有较好的应用前景。

An analytical method for the determination of 41 pesticide residues in crucian carp and bottom sediment was established using modified QuEChERS sample preparation and gas chromatography-tandem mass spectrometry(GC-MS/MS).The crucian carp samples were extracted by acetonitrile and ethyl acetate(V:V=1:1)and cleaned-up with 600 mg Alumina-B.The bottom sediment samples were extracted by ethyl acetate and cleaned-up with 600 mg Florisil and 150 mg Graphitized carbon black.The pesticide residues were analyzed by GC-MS/MS.A HP-5MS column was used for the separation,and the electron ionization(EI)was employed using dynamic multiple reaction monitoring(dMRM)mode for the detection.The matrix-matched external standard calibration curves were used for quantitative analysis.The method validation results indicated that in crucian carp,the instrumental limits of detection(LOD)for 41 pesticides were 0.05-2.5μg/L,and the limits of quantification(LOQ)were 0.1-5.0μg/kg for the method.The linear correlation coefficients(r)of the calibration curves were 0.9960-0.9999.The average recoveries at three spiked levels(LOQ,2LOQ and 10LOQ)were 73%-116%(n=6)with relative standard deviations(RSDs)of 0.65%-13%.In aquaculture sediment,the instrumental LODs for 41 pesticides were 0.05-2.5μg/L,and the LOQs were 0.1-5.0μg/kg for the method.r of the calibration curves were 0.9964-1.000.The average recoveries at three spiked levels(LOQ,2LOQ and 10LOQ)were 73%-104%(n=6)with RSDs of 0.051%-10%.The method was rapid,sensitive and accurate,and has a good application prospect in the detection of amides,triazines,phenyl pyrazoles,organochlorine and organophosphorus pesticide residues in crucian carp and bottom sediment.