Mass Spectrometry in Doping Control Analysis

Abstract

Mass spectrometry has become the most frequently employed technique in doping control analysis to identify prohibited compounds ever since their use has been banned by international federations. In combination with gas or liquid chromatography and various ionization methods such as electron or chemical ionization, electrospray, atmospheric pressure chemical ionization, atmospheric pressure photo ionization or matrix-assisted laser desorption ionization, numerous applications have been established enabling the sensitive and selective detection of prohibited drugs in matrices such as urine, blood, and hair. The classes of investigated compounds include low molecular weight drugs such as anabolic steroids, diuretics, β 2 -agonists and β-receptor blocking agents, and others as well as high molecular weight therapeutics, for instance plasma volume expanders based on polysaccharide structures (e.g. hydroxyethyl starch and dextran), hemoglobin-based oxygen therapeutics (e.g. Hemopure), or synthetic insulins. Assays for their identification are commonly based on extractive purification, chemical or enzymatic treatment (i.e. derivatization or degradation) followed by chromatographic and mass spectrometric analysis employing various modern analyzers such as quadrupole, ion trap, triple-quadrupole and magnetic-sector mass spectrometers allowing the sensitive and unambiguous qualitative as well as quantitative determination of xenobiotics in elite athletes' doping control samples. Moreover, the administration of drugs naturally occurring in human beings, for instance testosterone, is uncovered by carbon isotope ratio mass spectrometry that enables the differentiation between endogenous and exogenous sources. The comparison of δ-values obtained from endogenously produced steroids independent from testosterone and its metabolism with urinary testosterone and its metabolic products allow the determination of surreptitious applications.

Quantitative Determination of Metabolic Products of 19-Norandrostenediol in Human Plasma Using Gas Chromatography/Mass Spectrometry

“…Moreover, fragment ions resulting from cleavages of the steroid nucleus such as m/z 129 and 142 (Table 1) demonstrate the diagnostic character of electron ionization mass spectra used for qualitative and quantitative determination of target analytes. Although the ion at m/z 129 was generated from the steroidal D-ring under hydrogen rearrangement as substantiated by the presence of its deuterated counterpart at m/z 131 in the case of d 3 -NDiol, the fragment at m/z 142 resulted from the A-ring as reported in the literature earlier (Thevis and Schänzer, 2005).…”

Mass spectrometric analysis of androstan-17β-ol-3-one and androstadiene-17β-ol-3-one isomers

“…The product ion mass spectrum°of°the°protonated°molecule°s°of°12 (Figure°2a) demonstrated the efficient dissociation of the precursor ion upon application of a collision offset voltage of 30 V. In contrast to the earlier depicted dissociation patterns, the saturation of the steroid nucleus resulted in an abundant fragment ion at m/z 255 by elimination of two water°molecules° [31].°The°spectrum°was°dominated°by less diagnostic product ions separated by methylene units (14 u). These have also been observed in lower intensities during analysis of ␣,␤-unsaturated 3-keto steroids (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11), but the presence of double bonds did promote the formation of specific and characteristic fragment ions. m/z 215.…”

“…T he identification of natural and synthetic compounds using mass spectrometry is of paramount importance for documentation of use of illicit compounds by amateur and professional athletes. Elucidation of dissociation pathways of illegal substances using a variety of ionization and/or dissociation conditions is a robust technique for classification and identification of drugs and related compounds [1].Mass spectrometric studies on fragmentation of steroids using electron ionization (EI) were performed by Djerassi, Budzikiewicz, and coworkers [2][3][4][5][6][7][8]. Detailed studies have also been made employing steroid derivatives such as trimethylsilylated or acetylated compounds [9 -18].…”

“…T he identification of natural and synthetic compounds using mass spectrometry is of paramount importance for documentation of use of illicit compounds by amateur and professional athletes. Elucidation of dissociation pathways of illegal substances using a variety of ionization and/or dissociation conditions is a robust technique for classification and identification of drugs and related compounds [1].…”

“…Elucidation of dissociation pathways of illegal substances using a variety of ionization and/or dissociation conditions is a robust technique for classification and identification of drugs and related compounds [1].…”