气质法测定大棚土壤中的9种有机磷农药

GC/MS Method for Determination of 9 Organ Phosphorus Pesticide Residues in Soil of Greenhouse

建立气相色谱质谱法检测大棚蔬菜种植土壤中的9种有机磷类(毒死蜱、氧乐果、乙酰甲胺磷、马拉硫磷、乐果、甲基对硫磷、二嗪磷、三唑磷、治螟磷)农药的检测方法。样品经冰乙酸-乙腈溶液匀浆提取后,提取液经N-丙基乙二胺(PSA)、无水硫酸镁和C18进行分散萃取净化,浓缩后用丙酮定容至1 mL。经气相色谱-质谱仪定性定量检测,基质标准定量。结果表明, 9种有机磷类农药在0.05~5μg/m L范围内线性关系良好, R2均小于0.995;当加标浓度为0.5, 1.0和3.0 mg/kg时,得到的回收率范围为83.2%~98.2%;检出限为0.006~0.020 mg/kg;精密度RSD(n=6)为1.54%~4.23%。

A GC/MS method for determining 9 organophosphorus pesticide residues(chlorpyrifos, omethoate, acephate, malathion, dimethoate, parathion-methyl, diazinon, triazophos, and sulfotep) in soil of greenhouse was established. Samples were homogenized and extracted by acetonitrile-glacial acetic acid, the extracted solution then purified by PSA, anhydrous magnesium and C18. Purified solution was diluted with acetone to 1 mL, then was filtered and detected qualitatively and quantitatively by GC/MS, and quantified by matrix-match standard solution. The result showed that concentration of 9 organophosphorus pesticide residues showed good linear relationships in the range of 0.05-5 μg/mL, and the correlation coefficients were all above 0.995. The detection limits of 9 organ phosphorus pesticides were 0.006-0.020 mg/kg and the average recoveries at 3 spiked level of 0.5, 1.0 and 3.0 μg/mL varied from 83.2% to 98.2%. The RSD of precision was 1.54%-4.23%(n=6), and the relative standard deviation(RSD) of repeatability of 9 pesticide residues was 1.04%-3.36%(n=6).