Mass spectrometric characterization of efaproxiral (RSR13) and stanozolol using electrospray ionization with high resolution/high accuracy mass spectrometry

In the present study the collision-induced dissociation (CID) behavior of efaproxiral (RSR13) and stanozolol employing an LTQ-Orbitrap mass spectrometer with high resolution/high accuracy and MSn capabilities is shown, which allows the assignment of diagnostic product ions to defined regions of investigated molecules. Modifications of these structures would result in distinct shifts of characteristic product ions providing evidence for either metabolic alteration or intentional chemical manipulation of drugs. Both facts would be of utmost importance for doping control analysis to uncover surreptitious administrations of these drugs or related substances. The structural elucidation of drugs relevant for doping controls by tandem mass spectrometry concerted with MSn capabilities and high resolution-high accurate mass measurement provides information that can be utilized to identify further unknown metabolites or artificially modified analogues. Recent discoveries of synthetic growth promoters on the basis of so-called designer steroids has urged sports drug testing laboratories to extend screening procedures and develop complementary assays that allow a comprehensive detection of compounds with closely related structures to known therapeutic agents. Here, detailed knowledge of mass spectral behavior of target analytes is of great importance as well as for unambiguous identification of known therapeutics in routine screening analysis. Aus dem Text (geändert)