【摘要】 建立了气相色谱-质谱定量测定小龙虾中20种有机氯类混合农药残留的方法,并对提取溶剂、净化方法等分析条件进行优化。最终采用乙腈提取样品,乙酸乙酯-环己烷(1∶1)定容,凝胶渗透色谱(GPC)和氨基固相萃取柱(Carb/NH2)联合净化,以GC-MS检测,选择离子扫描(SIM)模式监测目标化合物的特征离子进行定性定量分析。20种化合物在0.01~1.0 mg/L范围内线性关系良好(r>0.994),各有机氯的检出限(S/N=3)为0.1~1.5μg/kg。分别对虾黄和虾尾进行5,10,20μg/kg 3个水平的加标实验,方法的回收率为71.3%~117.3%,相对标准偏差为0.6%~7.5%。该方法选择性好、灵敏度高,样品净化效果好,适用于小龙虾中有机氯类农药的多残留测定。更多还原

【Abstract】 A method was established for the quantitative determination of 20 organochlorine pesticides(OCPs) in crayfish by gas chromatography and mass spectrometry(GC-MS).The preparation and analytical conditions,such as extraction solvent,purification method and other analytical conditions were optimized.The samples were extracted with acetonitrile,and kept in constant volume with ethyl acetate-cyclohexane(1 ∶ 1).The extract was purified by gel permeation chromatography(GPC)combined with solid-phase extraction(SPE),and determined by GC-MS under selective ion scan(SIM) mode.Under the optimum conditions,the calibration curves of the compounds were linear in the range of 0.01-1.0 mg/L with correlation coefficients higher than 0.994,and the limits of detection(LOD,S/N = 3) were in the range of 0.1-1.5 μg/kg.The recoveries of target compounds in crayfish yellow and meat samples at three spiked concentration levels of 5,10,20 μg/kg were in the range of 71.3%-117.3%,with RSDs(n = 6) of 0.6%-7.5%.The method is sensitive,accurate and simple,and could be applied in the determination of 20 OCPs in crayfish.更多还原