【摘要】 为同时准确定量检测土壤中毒死蜱和氯氰菊酯残留量,建立了一种通过Qu ECh ERS样品预处理方法和气相色谱/微池电子捕获检测器法(GC/μECD)快速测定土壤中这2种农药残留的方法。样品用含0.1%乙酸的乙腈超声提取,适量N-丙基乙二胺(Primary secondary amine,PSA)和C18填料净化,GC/μECD检测,外标法定量。结果表明,毒死蜱和氯氰菊酯的响应分别在0.005~5.000 mg/L、0.01~5.00 mg/L质量浓度范围内线性良好,相关系数r均大于0.999,在0.01~0.50 mg/kg添加水平范围内,平均回收率在79.52%至96.30%之间,相对标准偏差(RSD,n=5)为2.03%~7.67%,检出限(信噪比大于3)分别为0.000 4 mg/kg、0.007 0 mg/kg,定量限(信噪比大于10)分别为0.005 mg/kg、0.010 mg/kg。基质效应对定量结果的影响可忽略不计。该方法操作简便、灵敏度高、干扰少,分析成本低,节省溶剂,适合于毒死蜱与氯氰菊酯在土壤中的残留分析与检测。更多还原

【Abstract】 To determine residues of chlorpyrifos and cypermethrin in soil simultaneously and accurately,a rapid analytical method based on the modified Qu ECh ERS(Quick,Easy,Cheap,Effective,Rugged and Safe) for sample preparation and gas chromatography-microelectron capture detector(GC/μECD) was established.The pesticides were extracted by acetonitrile containing 0.1% acetic acid with ultrasound assistance.The extracts were cleaned-up by using PSA(primary secondary amine) and C18 as adsorbents according to the method of Qu ECh ERS,determined by GC/μECD,and quantified by external standard method.The results showed that the calibration curves were linear in the ranges of 0.005-5.000 mg/L for chlorpyrifos and 0.01-5.00 mg/L for cypermethrin,with correlation coefficients higher than 0.999.The mean recoveries of two pesticides in soil ranged from 79.52% to 96.30% at spiked levels of 0.01-0.50 mg/kg with relative standard deviation(RSD,n = 5) of 2.03%-7.67%.The limits of detection(LOD,S/N> 3) for chlorpyrifos and cypermethrin were 0.000 4 mg/kg and 0.007 0 mg/kg and the limits of quantification(LOQ,S/N>10) were 0.005 mg/kg and 0.01 mg/kg,respectively.Matrix effect on the quantitative results could be neglected.The method is proved to be easy in operation,high in sensitivity,effective in purification,low at cost and solvent saving,which is applicable in analysis and determination of chlorpyrifos and cypermethrin in soil.更多还原