ESTANDARIZACIóN DE UN MéTODO ANALíTICO PARA EXTRACCIóN Y CUANTIFICACIóN DE CIPERMETRINA EN PASTOS

in this study, an analytical method has been developed to determine cypermethrin in grass matrices using direct immersion solid-phase microextraction (di-spme), coupled to gas chromatography with flame ionization detector (gc-fid). the optimized di-mefs experimental procedures to extract cypermethrin in grass matrix were: 5 g of the sample were heated with 10 ml of acetone 1% v/v in water during 10 min. 4 ml of this solution were used for extracting with a polydimethylsiloxane (pdms)-coated fiber at 60 °c and 500 rpm during 30 min. the analyte desorption was performed at 270 °c for 6 min. the proposed procedure showed linear behavior in the range tested (5-300 mg/l) with r2 of 0.999. the detection and quantification limits were 1.53 and 4.97 ng/ ml respectively with a standard deviation of 8.57% (n = 6). the method proposed in this paper allows determining cypermethrin in samples of grass to trace levels with a recovery of 99.08%.