Optimization of a multiresidue and multiclass analysis method for anabolic agents and β2-agonists in bovine urine by GC-MS/MS

A simple multiresidue and multiclass procedure is described for the simultaneous determination of anabolic agents and β2-agonists from 4 classes of prohibited substances of illegal use in food-producing animals, according to Council Directive 96/23/EC. The method involves analysis of hydrolysed urinary anabolic compounds using liquid–liquid extraction, with subsequent conversion to trimethylsilylether derivatives that are analysed by GC-MS/MS. The oven was set to an initial temperature of 140°C, was increased at a rate of 10°C/min to 300°C, and was held 3 min using an Ultra-1 capillary column. Optimization tests demonstrated good peak resolution and shape for all compounds. A pre-validation study was conducted to obtain an analytical test curve, which showed adequate results for all analytes. Cochran's test (C calculated