全自动固相萃取-GC-FPD法检测土壤中残留的马拉硫磷、甲基对硫磷和治螟磷

Determination of malathion,parathion methyl and fenitrophos in soil by SPE-GC-FPD

目的实验研究建立全自动固相萃取-GC-FPD法检测土壤中残留的马拉硫磷、甲基对硫磷和治螟磷的分析方法。方法土壤样品用丙酮提取后,上全自动固相萃取仪,控制流速20 mL/min,HLB固相萃取柱净化、富集,收集洗脱液,洗脱液氮吹至近干,丙酮溶解残渣,0.22μm滤膜率过后,上GC-FPD仪器,外标法定量检测。结果马拉硫磷、甲基对硫磷和治螟磷在浓度为0.02~2.0μg/mL范围内线性关系良好,相关系数均大于0.995;加标回收率在86.0~91.5%之间;检出限在0.005~0.012 mg/kg之间;重复性和精密度相对标准偏差(n=6)均在5.0%以内。结论该方法具有准确、快速、重复性好等优点,适用于土壤中马拉硫磷、甲基对硫磷和治螟磷残留的监测。

After being extracted with acetone,the soil sample was purified and enriched by HLB solidphase extraction column.The eluate was collected,the eluent nitrogen was blown to near dry,the residue was dissolved by acetone,and the membrane rate was 0.22μm.Then it was quantitatively detected by external standard method in GC-FPD instrument.Malathion,parathion methyl and fenitrophos had a good linear relationship in the concentration range of 0.02-2.0μg/ml,the correlation coefficient was greater than 0.995;the recovery rate was 86.0%-91.5%;the detection limit was 0.005-0.012 mg/kg;the relative standard deviation of repeatability and precision(n=6)was within 5.0%.This method has the advantages of accuracy,rapidity and good repeatability.