Identification of a probable new adrenergic agonist by nuclear magnetic resonance and mass spectrometry

Development of a metabolomic approach based on liquid chromatography-high resolution mass spectrometry to screen for clenbuterol abuse in calves

“…Indeed, there are many possible structures for b-agonists and as well as the illegal use of some well-known such as clenbuterol, salbutamol and bromobuterol, new compounds, which exhibit activity at the b2-adrenoreceptor have been progressively discovered. [6][7][8] Therefore, a range of compounds, either of known chemical structures but not yet included in the methods, or of unknown chemical structures, can be skipped during routine screening and confirmatory analysis. In addition, some practices consisting in the use of ''cocktails'' composed of mixtures of low amounts of several substances that exert a synergistic effect and exhibiting similar growth promotion properties have been reported.…”

Isobaric Tags for Relative and Absolute Quantification (iTRAQ)-Based Untargeted Quantitative Proteomic Approach To Identify Change of the Plasma Proteins by Salbutamol Abuse in Beef Cattle

“…To escape from residue detection during routine control, β 2 -agonists, such as salbutamol, are eliminated rapidly and usually below the limit of detection within several days . Several unknown β 2 -agonist analogues used illicitly as growth promoters in animal production have been discovered. − In addition, the use of low-dose “cocktails” that exert a synergetic effect and exhibit similar growth promotion characteristics has been reported in food animals . The use of both unknown β 2 -agonists and low-dose “cocktails” render routine screening approaches difficult to implement.…”