Determination of anxiolytic veterinary drugs from biological fertilizer blood meal using liquid chromatography high-resolution mass spectrometry.

A liquid environment-friendly agricultural material originating from animal blood, blood meal, was employed to detect anxiolytic veterinary drugs using a combination of liquid-liquid extraction (LLE) and positive electrospray ionization Orbitrap mass spectrometry. Every positive ion of the analytes was consistent with [M+H](+) , and the accurate mass analysis and mass spectral filtration with a 2-ppm mass tolerance window were applied to identify and quantitate the analytes and metabolites. The developed LLE method was validated with the lowest calibrated level, linearity (r(2) ), recovery, repeatability and the within-laboratory reproducibility, which were in the ranges of 0.3-1 µg/L, 0.9963-0.9995, 48.3-117.5%, 1.1-12.6% and 2.3-15.7%, respectively. The LLE method was compared with a solid-phase extraction (SPE) method; however, its recoveries were <70% for most of the analytes despite good repeatability of 1.2-7.4%. The analytes and the ascertained acepromazine, azaperone and xylazine metabolites were monitored in four actual liquid blood meal samples, and none of the targeted compounds were observed.