Wide-scope multi-residue analysis of pesticides in beef by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

Increasing pesticide contamination in foods of animal origin has made the wide-scope multi-residue analysis of pesticides an international concern. In this study, a sensitive and reliable multi-residue pesticide analysis method for beef was developed with the use of 129 pesticides to demonstrate the full scope of the method. The pesticides were extracted and purified using a modified QuEChERS technique and analysed using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. An orthogonal array design was employed for optimisation of the method, significantly scientising and simplifying the process. Method validation revealed satisfactory sensitivity with limits of quantification values ranging from 0.003 to 11.37 µg∙kg. Matrix effects ranged from 83.85% to 120.66%. Recovery at three spiking levels (20, 50, and 100 µg∙kg) were 70.51-128.12% and the intra-day and inter-day precisions were less than 20%, indicating good accuracy and precision.