In this study a multiresidue method for the determination of 24 pesticides in wheat, white flour and bran
using gas chromatography coupled to mass spectrometry with negative chemical ionisation and selected
ion monitoring (GC–MS (NCI–SIM)) was developed and validated. The QuEChERS method was used for
the extraction of different pesticides. The method was validated evaluating the following parameters: linearity,
limit of detention, limit of quantification, matrix effect as well as precision and accuracy, evaluating
the percentage of recovery at four different spike levels. The linear range used in the calibration
curves was from 1.0 to 100 lg L1 for wheat and 2.0 to 200 lg L1 for flour and bran, both with values
of r2 > 0.99. The recoveries had been considered satisfactory presenting values between 70% and 120%
with RSD < 20% for the majority of compounds.