RESUMO
A rapid and simple high-performance liquid chromatography-UV method was developed for the separation and quantification of salbutamol, ractopamine, and clenbuterol in pork. A mixture of acetonitrile-formic acid-ammonium acetate was used as the mobile phase to separate three ß-agonists on a C18 column with gradient. The effects of the addition of formic acid and ammonium acetate to mobile phases on the separation of ß-agonists were investigated. These additives can greatly improve the resolution and sensitivity. Under the optimized chromatographic condition, this separation does not need extra sample preparation. Complete baseline separation of three ß-agonists was achieved in < 20 minutes; the linear range is 0.2-50 µg/L with a correlation coefficient R2 value of > 0.99. Excellent method reproducibility was found by intra- and interday precisions with a relative standard deviation of < 3%. The detection limit (S/N = 3) was found to be <0.05 µg/L; this method can be used for routine screening of the ß-agonist residues in foods of animal origin before being identified by confirmatory methods.