Determination of benazolin-ethyl and haloxyfop-R-methyl residue in soil by high performance liquid chromatography

The analytical method of simultaneously determination of benazolin-ethyl and haloxyfop-R-methyl residue in soil was studied.Soil samples were extracted with methylene chloride-methanol mixture (9:1,V/V),and determined by high performance liquid chromatography (HPLC) with UV detector.Methanol-water (80:20,V/V) was used as mobile phase at a flow rate of 0.6 mL/min, and ultraviolet absorption wavelength was set at 225 nm for UV detector.Linear correlation of benazolin-ethyl and haloxyfop-R-methyl was 0.999 5 and 0.999 8 with concentration between 0.02 and 1 mg/L.When fortified from 0.05 to 1 mg/kg,the recoveries were 85.1% to 106.6%,with relative standard deriation(RSD) between 5.2% and 8.8%.The limit of detection of instrument for benazolin-ethyl and haloxyfop-R-methyl was 0.2 and 0.4 ng respectively,and the limit of quantification of the method was 0.05 mg/kg.The method can be used to analyze the residue of benazolin-ethyl and haloxyfop-R-methyl.