Internal validation of screening methodology for residues of epi-trenbolone, trenbolone, epi-nortestosterone and nortestosterone in bovine urine using immunoaffinity cartridges for sample clean-up Original Research Article

This multi-analyte procedure uses commercially available immunoaffinity chromatography (IAC) clean-up cartridges for extraction and clean-up, followed by determination of residues of epi-trenbolone (ETB), trenbolone (TB), epi-nortestosterone (epi-nandrolone) (ENT) and nortestosterone (nandrolone) (NT) in bovine urine by liquid-chromatography with UV absorbance detection. This single-laboratory internal validation included assessment of recoveries, repeatability, linearity, detection capability and cross-reactivity (specificity) with a suite of antibiotics and other hormonal growth promotants (HGPs). The method was validated for screening at a target level of 2.0 ng ml−1.