Human insulin-like growth factor-1 (IGF-1) is a peptide hormone that acts as a mediator of most of the somatotropic effects of growth hormone (GH). Therefore, it is supposed to be a biomarker indicating GH abuse in sports as well as diseases associated with a change in IGF-1 plasma concentration. It can be applied locally by injection to increase total protein and DNA content in tissues such as skeletal muscle -a highly desirable effect in various sports disciplines. In order to improve its growthpromoting properties, the primary structure of IGF-1 has been modified, yielding analogues such as des(1-3)IGF-1 and LONG TM R 3 IGF-1, which show a considerably reduced affinity to the respective binding proteins in plasma and, thus, an increased bioavailability at target tissues. Due to their capability to enhance performance, IGF-1 and its analogues belong to the prohibited list of the World Anti-Doping Agency. Hence, it was necessary to develop a reliable assay for the quantification of human IGF-1 as well as the detection of its derivatives. Immunoaffinity isolation and purification from 60 mL of plasma followed by liquid chromatography/electrospray ionisation tandem mass spectrometry enabled the unequivocal determination of all target analytes. Diagnostic product ions were characterised utilising an Orbitrap mass spectrometer with high resolution/high accuracy properties and employed for triple quadrupole MS/MS analysis. The described assay provided lower limits of detection (LLODs) between 20 and 50 ng/mL, recovery rates between 34-43% and a precision <15% at the LLOD as well as higher concentration levels. In order to prove the applicability of the developed assay, human plasma samples were analysed and the results were compared with the values obtained from a commercially available immunoradiometric assay (IRMA). Four of six samples resulted in concentration ratios with good correlation between both assays, whereas the absolute concentrations were lower for the presented procedure.
Synacthen is a synthetic analogue to human adrenocorticotropin, which plays an important physiological role by stimulating production of cortisol. In sports, corticosteroids as well as releasing factors (corticotropins) are prohibited according to the regulations of the World Anti-Doping Agency, and the misuse of Synacthen has been reported several times. Hence, an assay enabling the detection of Synacthen in doping control samples has been developed using immunoaffinity chromatographic isolation of Synacthen from human plasma combined with a concentration of collected fractions using solid-phase extraction. Unambiguous determination of the target analyte was accomplished using microbore liquid chromatography/electrospray ionization tandem mass spectrometry. Diagnostic product ions such as m/z 223 were characterized using high-resolution/high-accuracy Orbitrap mass spectrometry and employed for triple quadrupole MS/MS analysis. The established assay requiring 2 mL of plasma allowed a lower limit of detection (LLOD) at 100 fmol/mL, a recovery of 97% and a precision at the LLOD < 20%. Authentic plasma samples obtained from a patient undergoing a standard short Synacthen test were used to prove the applicability of the developed procedure.
Three nutritional supplements with "1-T matrix" were purchased by telephone order. The supplier of these supplements is a company from the UK, and the manufacturer is from the U.S. Aliquots of 1 g each were analyzed with gas chromatography / mass spectrometry and high pressure liquid chromatography with UV detector. In all supplements analyzed were found the anabolic-androgenic steroid metandienone. Metandienone, only available by prescription, was not declared on the labels. The concentrations of metandienone were 17.30 mg/g, 0.41 mg/g, and 0.96 mg/g for supplements 1, 2, and 3. In supplement 1, the concentrations of metandienone varied from capsule to capsule. Maximum concentrations of metandienone of 28.9 mg/g were detected. In addition to enormous health risks, the use of the analyzed supplements can lead to positive doping results for metandienone. The results of this study show that it is of major importance to improve the surveillance of the production and trade of dietary supplements. The first step should be a warning to be issued to consumers and the withdrawal of dietary supplements containing prescription drugs. Key Points:• All supplements analyzed contained the anabolic-androgenic steroid metandienone. • The use of metandienone is associated with a large number of adverse effects, especially in women, adolescents, and children. • The results of this study show that it is of major importance to improve the surveillance of the production and trade of dietary supplements.
Mass spectrometric approaches have been used to determine various peptide hormones in sports drug testing. While insulin-like growth factor-1 (IGF-1) and its synthetic analogs are qualitatively and/or quantitatively measured by liquid chromatography-tandem mass spectrometry after immunoaffinity purification, methods of uncovering doping rule violations with illegal applications of human growth hormone (hGH) have not yet been established using mass spectrometry-based assays. However, substantial information on the heterogeneity of hGH, splice variants and post-translational modifications with respective locations as elucidated by mass spectrometry are of utmost importance for improving currently employed immunological procedures.
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