In this work, an analytical method for the simultaneous detection and quantification of 11 macrolides (erythromycin A, gamithromycin, lincomycin, neospiramycin, pirlimycin, spiramycin, tildipirosin, tilmicosin, tulathromycin A and its metabolite CP-60300, and tylosin A) and 10 quinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, nalidixic acid, norfloxacin, oxolinic acid, and sarafloxacin) in muscle (bovine, ovine, porcine, equine, rabbit, poultry including laying hens, and fish) and kidney (bovine, ovine, porcine, equine) for human consumption was developed and validated according to Commission Implementing Regulation (EU) 2021/808. Sample preparation consisted of liquid extraction using a citrate–phosphate/EDTA buffer solution (McIlvaine buffer) followed by solid phase extraction for cleanup and UHPLC-MS/MS analysis. The developed method was comprehensively validated with regard to relative matrix effects (CVMF ≤ 20 %), linearity (R2 ≥ 0.98), accuracy (84–119 %), trueness (−16 to + 19 %), repeatability (2.1–20.0 %), reproducibility (3.0–25.0 %), selectivity, and robustness. The method limit of quantification values ranged from 2 to 40 µg kg−1, established as 0.1 × the lowest maximum residue limit (MRL) by species for the authorized antibiotics. Method applicability was demonstrated in six interlaboratory proficiency tests, and in the official control analyses of 1200 field samples of muscle and kidney.
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