Development and validation of a multiclass method for the determination of veterinary drug residues in honey

This study developed and validated an analytical method for simultaneous identification and quantification of 41 veterinary drugs in honey using liquid liquid extraction (LLE) and liquid chromatography coupled to quadrupole-Orbitrap high-resolution mass spectrometry (LC-Q-Orbitrap HRMS). The method was validated in accordance with Commission Implementing Regulation (CIR) EU 2021/808 at five different concentrations ranging from 0.075 to 50 μg/kg. The mean recoveries ranged from 70 to 105, while repeatability values were all below 17%. The linearity, as correlation coefficients (R2) ranged from 0.994 to 1. The limits of detection (LOD) and limits of quantification (LOQ) were in the range of 0.006–3.92 μg/kg and 0.011–6.54 μg/kg, respectively. The decision limit (CCα) and detection capability (CCβ) ranges were 0.0759–5.33 µg/kg and 0.0804–6.08 µg/kg, respectively. Of the 263 honey samples that were collected from local markets in Egypt, 47.5% had antibiotic residues. The mean concentration (µg/kg) and detection frequency (%) of the five most frequently detected antibiotics in the honey samples were as follows: trimethoprim (143.25 µg/kg and 39.9%), sulfamethoxazole (136.69 µg/kg and 30.7%), sulphadiazine (77.19 µg/kg and 18.6%), tylosin (184.37 µg/kg and 18.2%), and ciprofloxacin (185.33 µg/kg and 7.60%). The applicability of the developed method was proven through successful three proficiency testing (PT). The proposed method was demonstrated to be reliable for the simultaneous analysis of multi-class veterinary drugs in honey.