Analysis of beta-agonist residues in bovine hair: Development of a UPLC-MS/MS method and stability study

•Very rapid, sensitive and specific UPLC-MS/MS method was developed for the analysis of beta-agonists in bovine hair.•For the first time are reported the extraction and stability studies for the analyte clembuterol in real contaminated (positive) samples.•The method was validated in terms of linearity, precision, specificity, CCα and CCβ.

Beta-sympathomimetic compounds are widely used in therapy because of the bronchodilator, smooth muscle-relaxant and tocolytic properties. However, their growth promoting and performance enhancing effects are often subject to illegal use. The present work describes the development of a fast and reliable analytical multiresidue method for the confirmation 20 β-agonist compounds in animal hair. The procedure is based on alkaline digestion, LLE with organic solvents, SPE clean up and liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis, and is suitable for the public Official control of β-agonist residues in hair sample.Validation was performed according to Commission Decision 2002/657/EC requirements. Independent samples spiked with the investigated compounds in the range 0.2-10.0 μg kg−1 are showing intra-day and inter-day precision (RSD) lower than 17.8% and 19.7%, respectively. Linearity, measured in the range of 0.1-10.0 μg kg−1, resulted with a Pearson's r > 0.996. The decision limits (CCα) for the all investigated beta agonists resulted in the range 0.2-1.0 μg kg−1.Furthermore, the method was tested on real hair samples obtained from cattle, known as positive to clenbuterol, in order to check its effectiveness and the β-agonists stability.