Validación de un método multirresiduo para la determinación de medicamentos veterinarios en trucha y langostino

The study was aimed at developing and validate an analysis method to determine residues of 30 veterinary drugs in rainbow trout and shrimp specimens. The method involves extraction in dispersive solid phase with C18 and the subsequent detection through liquid chromatography coupled to mass spectrometry. Validation was done through determination of linearity, trueness (% of recovery), repeatability and intralaboratory reproducibility, limits of detection (LoD), limits of quantification (LoQ) selectivity and uncertainty. Recovery ranged from 70 to 120% and repeatability and intralaboratory reproducibility were lower than 20%. Selectivity was adequate, without interference peaks. Likewise, the ionic relationships met the confirmation criteria. The linearity was adequate, with determination coefficients (R²) above 0.99, except for sulfaquinolaxin in shrimp specimens (R² = 0,97). LoD and LoQ varied from 0,6 µg/kg to 12,8 µg/ kg. Limits of uncertainty ranged from 6 µg/kg to 49 µg/kg. The method was used to analyze 6 samples from different markets in Lima (Peru), identifying traces of some drugs included in the study. Our results show that the method is adequate for the analysis of veterinary drug residues and allow us to recommend its application in national monitoring programs, to assess the safety of rainbow trout and shrimp specimens from aquaculture.