RESUMO
Methods are validated by a process that defines the analytical requirements and confirms that the investigated method is capable of performing consistently. A quantitative and confirmatory method for determining the presence of ß-lactam and tetracycline multiresidues in avian, bovine, equine, and swine kidney tissues using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed, optimized, and validated. Analytes were extracted from the kidneys by a mixture of water and acetonitrile, and the extract was then purified with hexane and C18 (dispersive phase). The method was evaluated by the following parameters: linearity, matrix effect, specificity, decision limits (CCα), detection capability (CCß), accuracy, precision, trueness, limits of detection (LOD), limits of quantification (LOQ), and robustness. The validated method presented a broad linear study range and significant matrix effect. The limit of detection (LOD) was defined from 2.5 to 25.0 µg kg(-1), and the limit of quantification (LOQ) was defined from 5.0 to 50.0 µg kg(-1) for individual analytes. The resultant recovery values ranged from 98.1% to 107.3% in repeatability conditions and from 95.2% to 106% under intralaboratory reproducibility conditions for the studied analytes. It was concluded that the performance parameters demonstrated total method adequacy for detecting and quantifying ß-lactam and tetracycline residues in swine, equine, bovine, and avian kidneys.