QuEChERS/GC-MS快速分析土壤中的苯醚甲环唑残留

采用QuEChERS方法结合气相色谱-质谱(GC-MS)法建立了土壤中苯醚甲环唑残留的快速分析方法。用乙腈提取土壤中的苯醚甲环唑,基质固相分散净化后,GC-MS外标法定量。结果表明:方法具有快速、简便、高效、灵敏等优点,苯醚甲环唑在0.005~0.5 μ g/mL质量浓度范围内呈线性关系,相关系数达0.999。土壤中苯醚甲环唑添加水平为0.01~0.5 mg/kg时,平均回收率为74.2%~91.9%,相对标准偏差在4.59%~6.62%之间,检出限(LOD)为0.002 mg/kg,定量限(LOQ)为0.005 mg/kg。田间土壤消解动态试验表明:苯醚甲环唑在北京土壤中的消解半衰期为17.4 d,属于易降解农药。

Rapid determination of difenoconazole residue in soil using QuEChERS/GC-MS

A rapid analytical method was developed to detect difenoconazole residue in soil using QuEChERS with gas chromatography-mass spectrometry (GC-MS).Difenoconazole was firstly extracted from soil with acetronitrile,and then detected by GC-MS with external standard method after being cleaned up with matrix solid-phase dispersion.The results showed that the developed method was rapid,simple,high efficient and sensitive.A good linearity ranged from 0.005 to 0.5 μ g/mL was obtained and correlation coefficient was 0.999.The average recoveries were 74.2% -91.9% with RSD of 4.59% -6.62% at spiked level of 0.01 -0.5 mg/kg.The limit of detection (LOD) and limit of quantification (LOQ) was 0.002 and 0.005 mg/kg,respectively.The results of residue decline study in field experiment showed that the half-life of difenoconazole in Beijing soil was 17.4 d.Difenoconazole belongs to the type of easily degradating compound is soil.