Qualitative screening of 116 veterinary drugs in feed by liquid chromatography-high resolution mass spectrometry:...

Veterinarian and human pharmaceuticals may be intentionally added to animal feed to enhance animal production. Monitoring these substances is necessary for protecting the consumers. In this work, a screening method covering 116 human and veterinary drugs has been developed and validated in five types of animal feed at 0.02 and 0.2 mg kg(-1). After a simple extraction and dilution, the samples were analysed by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS). Nearly all compounds tested were detected at 0.02 mg kg(-1), based on the presence of the accurate-mass (de)protonated molecule. However, the identification using a second accurate-mass ion was more problematic at this level. Finally, the procedure was applied to 22 feed samples, where trimethoprim, robenidine, or α- and β-nandrolone were detected and identified. The potential applicability of the method to quantitative analysis of the compounds detected in the samples was also evaluated.