[Determination of carbendazim residue in orange and soil using high performance liquid chromatography]

An analytical method of high performance liquid chromatography (HPLC) was established for determining carbendazim residue in orange and soil. The residue was extracted with alkaline acetonitrile, cleaned-up by NH2 solid-phase extraction (SPE), separated on a Luna C18 column (250 mm x 4.6 mm, 5 microm) using 10 mmol/L ammonium acetate solution (A) and acetonitrile (B) as the mobile phases with the gradient elution (0-->15 min, 20% B; 15-->25 min, 80% B; 25-->35 min, 20% B) at a flow rate of 1.0 mL/min, and detected at 275 nm. The method showed a linear relationship between peak area and concentration at the range of 0.02 - 5.0 mg/L for carbendazim. The average recoveries of the method ranged from 89.2% to 102% with the relative standard deviations of 1.8% - 9.1% at spiked level of 0.05 - 0.5 mg/kg. The limit of detection was 0.05 mg/kg in sarcocarp and soil, and that was 0.1 mg/kg in pericarp and whole orange. The method is characterized by simplicity, higher sensitivity and accuracy.