Determination of metaflumizone residues in cabbage and soil using ultra-performance liquid chromatography/ESI-MS/MS

A simple confirmatory method for the determination of metaflumizone in cabbage tissues and soil samples using ultra-performance liquid chromatography-ESI/MS/MS is presented. Metaflumizone residues in cabbage and soils were extracted with acetonitrile and an aliquot was cleaned up with primary and secondary amine. Two precursor product ion transitions for metaflumizone were measured and evaluated to provide the maximum degree of confidence in results. Under ESI negative conditions, quantitation was achieved by monitoring the fragment m/z = 302 and qualitative fragment m/z = 116.5 while also collecting their parent ion m/z = 505.5. Average recoveries for cabbage and soil at four different levels (0.01, 0.05, 1 and 5 mg/kg) ranged from 77.6 to 87.9% with RSD of 3.5-7.9% and RSD(R) of 4.5-7.1%. The coefficients of determination of R(2) > or = 0.9991 were achieved for metaflumizone calibration curves from 0.01 to 5.0 microg/mL. The metaflumizone LODs in cabbage and soil were determined to be both 0.001 mg/kg with a LOQ of 0.004 mg/kg. This method was able to demonstrate quantitative recoveries and provide confirmatory data for the identification of metaflumizone residues in cabbage tissues and the surrounding soils following commercial application.