Fast GC, GC-MS and sample preparation methods for pesticide residue analysis in non-fatty baby food

Possibilities and limitations of a bench top mass spectrometric detector (MSD) in selective ion monitoring mode (SIM) and electron capture detector (ECD) in fast gas chromatography (GC) with narrow bore columns of samples with complex matrices at ultra trace levels of pesticide residues were studied and compared.. Various injection systems were searched (splitless, on-column, programmable temperature vaporiser). Two narrow-bore capillary columns with the same stationary phase, phase ratio and separation power but different I.D. 0.15 mm and 0.10 mm were compared with regards to their advantages, practical limitations and applicability in fast GC under the conditions of separation/speed trade-off. Fast GC-MS detection was applied to determination of selected pesticides in apples, the common raw material for baby food production in Slovakia, at the concentration level ≤10 μg kg maximum residual limit (MRL). Four sample preparation methods were compared for the ultratrace analysis of pesticide residues in baby food. The effectiveness of clean-up of the final extract was determined. Optimization of extraction and GC measurements as well as the simplifying of the whole process of sample preparation were carried out.