Residue analysis of bifenazate in citrus and soil

The high performance liquid chromatographic method was described for the determination of bifenazate in citrus and soil.The citrus samples were ultrasonic-extracted with hexane-ethyl acetate and cleaned up by Alkali alumina,the soil samples were ultrasonic-extracted with carbon disulfide-acetone,and then detected by HPLC-DAD.The linear relationship of bifenazate was found better in the concentration range from 0.05 to 10.00 μg/mL with the linear correlation of 0.999 4.In the present method,the lowest limit of quantification was 0.02 mg/kg. The average recovery varied from 87.12% to 98.93%,and the RSD ranged from 2.62% to 7.32%at the addition level of 0.02-1 mg/kg.The method accuracy,sensitivity and stability are in line with the requirement of pesticide residue analysis.