Pesticide Residue Methods

Category Others
Class Name Multi-Residue Method
Method Title AOAC Official Method 2007.01 Pesticide Residues in Foods by Acetonitrile Extraction and Partitioning with Magnesium Sulfate Gas Chromatography/Mass Spectrometry and Liquid Chromatography/Tandem Mass Spectrometry First Action 2007
Method Date 2007/01/01
Method Type Screening
Scope and Application A Multi Pesticide Residue Method for the analysis of a side range of pesticides in crop matrices.
Method Summary In brief, a well-chopped food sample along with 1 mL of 1pct acetic acid, HOAc, in MeCN and 0.5 g anhydrous MgSO4:NaOAc, 4:1, w:w per g sample are added to a centrifuge tube or bottle, which is shaken and centrifuged. A portion of the MeCN extract, upper layer is added to anhydrous MgSO4:PSA sorbent, 3:1 w:w 200 mg per 1 mL extract, mixed, and centrifuged. This final extract is transferred to autosampler vials for analysis by gas chromatography:mass spectrometry (GC:MS) and liquid chromatography tandem mass spectrometry, LC MS MS to identify and determine a wide range of pesticide residues. To achieve less than10 ng per g detection limits in modern GC:MS, large volume injection, LVI, of 8 mcL is typically needed, or the final extract can be concentrated and solvent exchanged to toluene, 4 g per mL, in which case 2 mcL splitless injection is used. Both GC MS and LC MS MS techniques are prone to matrix effects in pesticide residue analysis, albeit for different reasons. To account for these effects, matrix-matched calibration was conducted (calibration standards in solvent solution may also be used if matrix effects are shown not to occur). Due to the situation that some laboratories had LVI capability and others did not, the necessary amounts of matrix blank and final extract volume was different for some laboratories than others. Depending on the water content of the matrix, a 15 g sample typically yields 11-14 mL of initial MeCN extract after centrifugation. In dispersive-SPE, roughly half of the extract is lost to the powders, thus about 6-7 mL of final extract can be expected for a 15 g sample. Two options were provided in the protocol to account for the different situations among the laboratories.
Applicable Concentration Range LOQ 0.01 ng per g
QC Requirements See Method
Method Performance/Validation See Method
Method Source
Method SOP PDF icon SOP 
Citation J. AOAC Int. 90, 485 (2007)