This application note describes a simple and high-throughput method for the analysis of 213 pesticides in leek and garlic using an Agilent QuEChERS kit combined with Agilent gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). A matrix-matched standard calibration method was used to avoid quantitation bias from matrix interference. It shows that the method has a linearity more than two orders of magnitude (2–400 µg/kg), with linear regression coefficients (R2) of 0.99 or above for the majority of pesticides. The limits of quantification (LOQs) ranged between 2 and 10 µg/kg, and the majority of the pesticides had an LOQ of 2 µg/kg, which is below the regulatory maximum residue limits. A spiking test showed that most recoveries at 2, 5, 10, 20, 50, 100, and 200 µg/kg were in the range of 80–120% (n = 6) with associated RSDs below 20%. Leek and garlic samples were analyzed for method application. This method can be applied for routine analysis of these pesticide residues in leek and garlic.
Publication number: 5991-6381EN.pdf
Publication Date: October 26, 2015