Pesticide Residue Methods

Category Others
Class Name Pesticide Specific Enforcement Method, Bifenazate and related Metabolites
Method Title Analytical Method for the Analysis of 02341 and 03598 in Apples and Citrus
Method Date 1998/03/23
Method Type Quantitative
Scope and Application Analysis for bifenazate and related metbolite residues Analysis of fruits (apples and citrus) Can be used with minor modifications for most crop matrices HPLC, Coloumetric detection
Method Summary Residues of D2341 and D3598 were extracted from the homogenized matrix twice with acetonitrile / acetic acid in a blender. The extracts were filtered into a 250 mL graduated cylinder, and the volume was brought to exactly 250 mL with acetonitrile. A 50 mL aliquot of the extract was partitioned with 2 pct aqueous sodium sulfate and methylene chloride. The organic phase from the partition was filtered through anhydrous sodium sulfate and concentrated to near dryness by rotary evaporation. The extract was then diluted with HPLC mobile phase containing ascorbic acid prior to HPLC analysis with oxidative coulometric detection. Residues of 02341 and 03598 are measured as D2341 after ascorbic acid reduction of D3598. The ascorbic acid reduction of D3598 to D2341 is necessary to ensure that total recovery of D2341 plus D3598 is accurately measured. This is because D2341 may oxidize rapidly to D3598 in solvent extracts of crops. Without ascorbic acid, the relative concentrations of D2341 and D3598 in the sample change during the time of analysis. Ascorbic acid ensures that the concentration of D2341 remains stable over the period of sample analysis. Recovery of D3598 is validated by the fortification of matrix with only 03598 and measuring the D2341 peak in the chromatogram after reduction.
Applicable Concentration Range Estimated LOQ: 0.01 mg/Kg
QC Requirements See Attached Method
Method Performance/Validation See Attached Method
Method Source IR-4, Ricerca
Method SOP PDF icon SOP 
Citation Ricerca, Inc. Document Number: 6998-97-0237-CR-001