Bioanalysis of beta 2-agonists by hyphenated chromatographic and mass spectrometric techniques

Recent reports on the misuse of beta 2-agonists, both as stimulants and as "anabolic agents" in sports, highlight the importance of screening and confirmation methods for these compounds in anti-doping control procedures. Although only a few analytical methods have been developed for this purpose, the large experience gained, both in pharmacokinetic studies and above all in the control of the residues of beta 2-agonists in animal fluids and tissues, can be of great help in the anti-doping field. This paper reviews single-residue (SR) and multi-residue (MR) methods developed for the analysis of beta 2-agonists in urine, plasma and hair samples, based on hyphenated chromatographic and mass spectrometric techniques, published in the last ten-year period. The evolution from GC-MS analysis after derivatization, with particular attention to the features of different proposed derivatives, to the most recent applications of coupled-column liquid chromatography (LC-LC) combined with tandem mass spectrometric detection (MS-MS) via a thermospray (TSP) interface is illustrated, and future perspectives in the field are outlined.