Pesticide residue analysis in crops by LC-MS/MS method

Abstract

An LC-MS-MS assay is described for fluazifop residue analysis in crops. The residues are extracted with acidified organic solvent, the esters and conjugates are hy¬drolysed with 6.01 M hydrochloric acid, then the extracts are cleaned-up by solid phase extraction using C2(EC) and Si cartridges in tandem. Quantitative analysis is performed by gradient liquid chromatography coupled to triple quad- rupole mass spectrometer using atmospheric pressure chemical ionization. All fluazifop-P-butyl, free fluazifop- P and any conjugates are quantified as fluazifop-P. The limit of quantification is 0.012-0.054 mg/kg depending on crop matrices. The clean-up method is also suitable for LC-UV analysis with a compromise in higher limit of quantification 0.052-0.22 mg/kg