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.