Does further clean-up reduce the matrix enhancement effect in gas chromatographic analysis of pesticide residues in food?

摘要: Sample extracts of apples, peas, green beans, oranges, raspberries, clementines, carrots, and wheat obtained using the Food Drug Administration (acetone extraction) Canadian Pest Management Regulatory Agency (acetonitrile multiresidue methods for pesticides were subjected to clean-up different solid-phase extraction (SPE) cartridges in an attempt reduce or eliminate matrix enhancement effect. The effect is related blocking active sites on injector liner by components, thereby increasing signal presence versus standards solvent which themselves interact with sites. Graphitized carbon black (GCB) was often used combination various anion-exchange SPE cartridges. then spiked organophosphorus insecticides. These process compared acetone same concentration gas chromatography flame photometric detection ion trap mass spectrometric detection. varied from little no some (e.g. chlorpyrifos, malathion) >200% case certain susceptible pesticides. GCB removed color components but showed reducing itself. not, substantially reduced did not it.