Determination of pesticide residues in food using some recent applications in gas chromatography coupled with tandem mass spectrometry

Abstract

One of the major problems in the GC analysis is the unexpected high recovery of matrix-matched standard calibration when compared with matrix-free standard calibration, also known as the “matrix-induced chromatographic response enhancement effect”. The matrix-induced signal enhancement effect happens when an analyte is retained or decomposed by active sites in the inlet (e.g. liner and initial portion of the column). Pesticides with polar structures, e.g., hydroxy, amino, and phosphate functional groups, have a higher chance of binding and reacting with glass and metal surfaces in a heated gaseous state than nonpolar pesticides, e.g., organic chlorinated pesticides. In the presence of plant-derived matrix components in the extract, the interaction of pesticides with active sites is significantly decreased as these matrix components, that are present in excess, occupy most of the active sites, allowing the pesticide molecules to go through the GC system with strongly reduced surface interactions. Therefore, analyte protectants are added to the mixture prior to injection to mask the active sites in the liner. Considering previous studies, this study aimed to find the