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Complementary information concerning the suspected interindividual transmission of GW1516, a substance prohibited in sport, through intimate contact: a case report. Forensic Toxicol 2024:10.1007/s11419-024-00689-x. [PMID: 38704758 DOI: 10.1007/s11419-024-00689-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 04/14/2024] [Indexed: 05/07/2024]
Abstract
PURPOSE Inadvertent and/or unknowing exposure to drugs and drug residues has been frequently debated in situations of so-called adverse analytical finding (AAF) in the context of sports drug testing programs. Transfer of drug residues via unprotected intercourse is a conceivable scenario but scientific data and authentic case reports are scarce. Herein, investigations into two AAFs with the peroxisome proliferator-activated receptor delta (PPARδ) agonist GW1516 are reported and discussed. METHODS To probe for a contamination scenario involving sexual intercourse, two assays were used to determine semenogelin in human urine, with one employing an immunochromatographic lateral flow approach and another based on liquid chromatography-tandem mass spectrometry. Further, drug-residue testing using patients' ejaculate was conducted by utilizing liquid chromatography in conjunction with a triple quadrupole mass spectrometer, followed by re-analysis of suspect samples (i.e., samples indicating the presence of relevant compounds) using high resolution/high mass accuracy mass spectrometry. RESULTS In one case, but not the other, the possibility of intimate contact as the source of the AAF was confirmed after a thorough investigation of potential contamination scenarios. Subsequent research revealed analytical evidence for the presence of seminal fluid in one of the female athlete's doping control urine samples, and the analysis of clinical ejaculate specimens provided first data on an authentic concentration level of GW1516 and its metabolites in human seminal fluid. CONCLUSIONS The combined facts substantiate the possibility of an AAF caused by unprotected sexual intercourse and the plausibility of the case-related arguments.
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DropWise: current role and future perspectives of dried blood spots (DBS), blood microsampling, and their analysis in sports drug testing. Crit Rev Clin Lab Sci 2023; 60:41-62. [PMID: 35938300 DOI: 10.1080/10408363.2022.2103085] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
For decades, blood testing has been an integral part of routine doping controls. The breadth of information contained in blood samples has become considerably more accessible for anti-doping purposes over the last 10 years through technological advancements regarding analytical instrumentation as well as enhanced sample collection systems. Particularly, microsampling of whole blood and serum, for instance as dried blood spots (DBS), has opened new avenues in sports drug testing and substantially increased the availability and cost-effectiveness of doping control specimens. Thus, microvolume blood specimens possess the potential to improve monitoring of blood hormone and drug levels, support evaluation of circulating drug concentrations in competition, and enhance the stability of labile markers and target analytes in blood passport analyses as well as peptide hormone and steroid ester detection. Further, the availability of the fraction of lysed erythrocytes for anti-doping purposes warrants additional investigation, considering the sequestering capability of red blood cells (RBCs) for certain substances, as a complementary approach in support of the clean sport.
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Detectability of oxandrolone, metandienone, clostebol and dehydrochloromethyltestosterone in urine after transdermal application. Drug Test Anal 2022; 14:1744-1761. [PMID: 35947101 DOI: 10.1002/dta.3355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 07/29/2022] [Accepted: 08/07/2022] [Indexed: 11/11/2022]
Abstract
Situations of both, intentional as well as inadvertent or accidental doping, necessitate consideration in today's doping controls, especially in the light of the substantial consequences that athletes are facing in case of so-called adverse analytical findings. The aim of this study was to investigate, whether a transdermal uptake of doping substances would be possible. In addition to the period of detectability of the particular substances or respective characteristic metabolites, the possibility of deducing the route of administration by metabolite patterns was also assessed. Twelve male subjects were included in the study. Four common anabolic androgenic steroids (AAS) were dissolved in dimethylsulfoxide (DMSO) to facilitate transdermal administration on different skin regions. One half of the test persons received only oxandrolone (17α-methyl-2-oxa-4,5α-dihydrotestosterone), the other half was applied a mixture of oxandrolone, metandienone (17β-hydroxy-17-methylandrosta-1,4-dien-3-one), clostebol (4-chlorotestosterone-17β-acetate) and dehydrochloromethyltestosterone (DHCMT). Urine samples were collected 1 hour, 6 hours and one sample per day for the next 14 consecutive days. Measurements were conducted on a GC-MS/MS or LC-MS/MS system. Substance findings were obtained at least 1 day after application on nearly all skin locations. The results indicated inter-individual variability in detection windows, also varying between the different analytes and possible impact of skin location and skin thickness, respectively. Nevertheless, a rapid and rather long detectability of all substances (or respective metabolites) was given, in some cases within hours after administration and for up to 10-14 days. Hence, the transdermal application or exposure to the investigated AAS is a plausible scenario that warrants consideration in anti-doping.
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Nachweis synthetischer Insuline in Doping-Analytik und Forensik. Rechtsmedizin (Berl) 2019. [DOI: 10.1007/s00194-019-00347-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Analyses of Meldonium (Mildronate) from Blood, Dried Blood Spots (DBS), and Urine Suggest Drug Incorporation into Erythrocytes. Int J Sports Med 2016; 37:500-2. [DOI: 10.1055/s-0036-1582317] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Nickel in equine sports drug testing - pilot study results on urinary nickel concentrations. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:982-984. [PMID: 26969941 DOI: 10.1002/rcm.7528] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 02/01/2016] [Indexed: 06/05/2023]
Abstract
RATIONALE The issue of illicit performance enhancement spans human and animal sport in presumably equal measure, with prohibited substances and methods of doping conveying both ways. Due to the proven capability of unbound ionic cobalt (Co(2) (+) ) to stimulate erythropoiesis in humans, both human and equine anti-doping regulations have listed cobalt as a banned substance, and in particular in horse drug testing, thresholds for cobalt concentrations applying to plasma and urine have been suggested or established. Recent reports about the finding of substantial amounts of undeclared nickel in arguably licit performance- and recovery-supporting products raised the question whether the ionic species of this transition metal (Ni(2) (+) ), which exhibits similar prolyl hydroxylase inhibiting properties to Co(2) (+) , has been considered as a substitute for cobalt in doping regimens. METHODS Therefore, a pilot study with 200 routine post-competition doping control horse urine samples collected from animals participating in equestrian, gallop, and trotting in Europe was conducted to provide a first dataset on equine urinary Ni(2) (+) concentrations. All specimens were analyzed by conventional inductively coupled plasma mass spectrometry (ICP-MS) to yield quantitative data for soluble nickel. RESULTS Concentrations ranging from below the assay's limit of quantification (LOQ, 0.5 ng/mL) up to 33.4 ng/mL with a mean value (± standard deviation) of 6.1 (±5.1) ng/mL were determined for the total nickel content. CONCLUSIONS In horses, nickel is considered a micronutrient and feed supplements containing nickel are available; hence, follow-up studies are deemed warranted to consolidate potential future threshold levels concerning urine and blood nickel concentrations in horses using larger sets of samples for both matrices and to provide in-depth insights by conducting elimination studies with soluble Ni(2) (+) -salt species. Copyright © 2016 John Wiley & Sons, Ltd.
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Solutions Advertised as Erythropoiesis-stimulating Products were Found to Contain Undeclared Cobalt and Nickel Species. Int J Sports Med 2016; 37:82-4. [DOI: 10.1055/s-0035-1569350] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Methotrexate reduces HbA1c concentration but does not produce chronic accumulation of ZMP in patients with rheumatoid or psoriatic arthritis. Scand J Rheumatol 2016; 45:347-55. [PMID: 26726793 DOI: 10.3109/03009742.2015.1105290] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVES The mechanism by which methotrexate (MTX) improves glucose homeostasis in patients with rheumatoid (RA) and psoriatic arthritis (PsA) remains undetermined. Animal studies indicate a role for intracellular accumulation of 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranosyl 5'-monophosphate (ZMP) but this has not been directly demonstrated in humans. We explored whether accumulation of ZMP is associated with improvements in glucose homeostasis during MTX therapy. METHOD MTX-naïve, non-diabetic RA (n = 16) and PsA (n = 10) patients received uninterrupted MTX treatment for 6 months. To evaluate whether ZMP accumulated during MTX therapy, we measured the concentration of ZMP in erythrocytes and the concentration of its dephosphorylated derivative 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) in urine using liquid chromatography mass spectrometry (LC-MS/MS). To assess glucose homeostasis, we determined the concentration of glycated haemoglobin (HbA1c) and homeostasis model assessment of insulin resistance [HOMA-IR: fasting glucose (mmol/L) × fasting insulin (μU/mL)/22.5]. RESULTS Erythrocyte ZMP and urinary AICAR concentrations did not increase during 6 months of MTX therapy. HbA1c concentration was reduced from 5.80 ± 0.29% at baseline to 5.51 ± 0.32% at 6 months (p < 0.001), while HOMA-IR remained unaltered. Reduction in HbA1c concentration was not associated with increased ZMP or AICAR concentrations. CONCLUSIONS MTX therapy probably does not produce a chronic increase in erythrocyte ZMP or urinary AICAR concentrations. Collectively, our data do not support the hypothesis that MTX improves glucose homeostasis through chronic accumulation of ZMP.
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Metabolism of Oral Turinabol by Human Steroid Hormone-Synthesizing Cytochrome P450 Enzymes. Drug Metab Dispos 2015; 44:227-37. [DOI: 10.1124/dmd.115.066829] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 12/07/2015] [Indexed: 01/06/2023] Open
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SAT0219 Methotrexate-Induced Reduction in Concentration of HBA1C in Rheumatoid and Psoriatic Arthritis is Not Correlated with Sustained Increase in Erythrocyte ZMP or Urinary Aicar Concentration. Ann Rheum Dis 2015. [DOI: 10.1136/annrheumdis-2015-eular.2329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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In vitro synthesis and characterisation of three fenoterol sulfoconjugates detected in fenoterol post-administration urine samples. Anal Bioanal Chem 2013; 405:9477-87. [DOI: 10.1007/s00216-013-7383-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 09/16/2013] [Accepted: 09/16/2013] [Indexed: 11/30/2022]
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AOD-9604 does not influence the WADA hGH isoform immunoassay. Drug Test Anal 2013; 5:850-2. [DOI: 10.1002/dta.1557] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 08/16/2013] [Accepted: 08/29/2013] [Indexed: 11/11/2022]
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New potential markers for the detection of boldenone misuse. J Steroid Biochem Mol Biol 2012; 132:239-46. [PMID: 22664392 DOI: 10.1016/j.jsbmb.2012.05.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 05/17/2012] [Accepted: 05/18/2012] [Indexed: 10/28/2022]
Abstract
Boldenone is one of the most frequently detected anabolic androgenic steroids in doping control analysis. Boldenone misuse is commonly detected by the identification of the active drug and its main metabolite, 5β-androst-1-en-17β-ol-3-one (BM1), by gas chromatography-mass spectrometry (GC-MS), after previous hydrolysis with β-glucuronidase enzymes, extraction and derivatization steps. However, some cases of endogenous boldenone and BM1 have been reported. Nowadays, when these compounds are detected in urine at low concentrations, isotope ratio mass spectrometry (IRMS) analysis is needed to confirm their exogenous origin. The aim of the present study was to identify boldenone metabolites conjugated with sulphate and to evaluate their potential to improve the detection of boldenone misuse in sports. Boldenone was administered to a healthy volunteer and urine samples were collected up to 56h after administration. After a liquid-liquid extraction with ethyl acetate, urine extracts were analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS) using electrospray ionisation in negative mode by monitoring the transition of m/z 365-350, specific for boldenone sulphate. Boldenone sulphate was identified in the excretion study urine samples and, moreover, another peak with the same transition was observed. Based on the MS/MS behaviour the metabolite was identified as epiboldenone sulphate. The identity was confirmed by isolation of the LC peak, solvolysis and comparison of the retention time and MS/MS spectra with an epiboldenone standard. These sulphated metabolites have not been previously reported in humans and although they account for less than 1% of the administered dose, they were still present in urine when the concentrations of the major metabolites, boldenone and BM1, were at the level of endogenous origin. The sulphated metabolites were also detected in 10 urine samples tested positive to boldenone and BM1 by GC-MS. In order to verify the usefulness of these new metabolites to discriminate between endogenous and exogenous origin of boldenone, four samples containing endogenous boldenone and BM1, confirmed by IRMS, were analysed. In 3 of the 4 samples, neither boldenone sulphate nor epiboldenone sulphate were detected, confirming that these metabolites were mainly detected after exogenous administration of boldenone. In contrast, boldenone sulphate and, in some cases, epiboldenone sulphate were present in samples with low concentrations of exogenous boldenone and BM1. Thus, boldenone and epiboldenone sulphates are additional markers for the exogenous origin of boldenone and they can be used to reduce the number of samples to be analysed by IRMS. In samples with boldenone and BM1 at the concentrations suspicion for endogenous origin, only if boldenone and epiboldenone sulphates are present, further analysis by IRMS will be needed to confirm exogenous origin.
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Identification and characterization of urinary prenylamine metabolites by means of liquid chromatography-tandem mass spectrometry. Drug Test Anal 2012; 4:701-16. [PMID: 22786790 DOI: 10.1002/dta.1388] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 06/13/2012] [Accepted: 06/18/2012] [Indexed: 11/09/2022]
Abstract
Prenylamine is a vasodilator of phenylalkylamine structure and was used for the treatment of angina pectoris, until reports of undesirable effects including ventricular tachycardia led to a decreasing use of the drug in the 1980s. Metabolic N-dealkylation of orally ingested prenylamine can liberate amphetamine in humans and cause positive findings for amphetamine in doping and forensic analysis. In 2010, the World Anti-Doping Agency (WADA) classified prenylamine as a non-specified stimulant according to the 2010 Prohibited List, thus banning its use in sports in-competition. Supporting the development of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) based detection method, a post-administration urine sample following a single oral prenylamine ingestion (Segontin(®) 60 mg) was analyzed for urinary metabolites. The LC-separated analytes were ionized in positive electrospray ionization (ESI) mode and detected as protonated ions using an AB Sciex TripleTOF 5600 quadrupole-time-of-flight hybrid mass spectrometer. Over 40 phase I metabolites were detected, including previously unknown mono- bis-, tris- and tetra-hydroxylated prenylamine, several hydroxylated and methoxylated prenylamine metabolites and (hydroxylated) diphenylpropylamine. Investigation of the collision-induced dissociation behaviours of the metabolites by high resolution/high accuracy mass spectrometry allowed for the assignment of the nature and the site of observed metabolic transformations. The most abundant phase I metabolite was confirmed as p-hydroxy-prenlyamine by chemical synthesis and stable isotope labelling of reference material. An existing routine screening assay based on direct injection and LC-MS/MS analysis of urine was modified and validated according to common guidelines, in order to allow for the detection of p-hydroxy-prenylamine in sports drug testing. The assay demonstrated the ability to detect the target metabolite at 0.1 ng/ml at intra- and inter-day imprecisions below 10%.
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Clenbuterol - regional food contamination a possible source for inadvertent doping in sports. Drug Test Anal 2012; 4:534-8. [DOI: 10.1002/dta.1330] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 01/17/2012] [Indexed: 11/05/2022]
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Di(2-ethylhexyl) phthalate metabolites as markers for blood transfusion in doping control: Intra-individual variability of urinary concentrations. Drug Test Anal 2011; 3:892-5. [DOI: 10.1002/dta.377] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 08/26/2011] [Accepted: 09/20/2011] [Indexed: 01/30/2023]
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High-throughput screening for various classes of doping agents using a new ‘dilute-and-shoot’ liquid chromatography-tandem mass spectrometry multi-target approach. Drug Test Anal 2011; 3:836-50. [DOI: 10.1002/dta.372] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 08/31/2011] [Accepted: 09/12/2011] [Indexed: 11/11/2022]
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Determination of Vasopressin and Desmopressin in urine by means of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry for doping control purposes. Anal Chim Acta 2011; 707:107-13. [DOI: 10.1016/j.aca.2011.09.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/16/2011] [Accepted: 09/17/2011] [Indexed: 11/16/2022]
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Evaluation of commercially available assays for the measurement of equine insulin. Domest Anim Endocrinol 2011; 41:81-90. [PMID: 21741576 DOI: 10.1016/j.domaniend.2011.05.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 04/08/2011] [Accepted: 05/02/2011] [Indexed: 11/20/2022]
Abstract
Determining circulating equine insulin concentrations is becoming increasingly important in equine clinical practice and research. Most available assays are optimized for human medicine, but there is strong equine cross-reactivity because of the highly conserved nature of insulin. To identify an accurate and reliable assay for equine insulin, 6 commercial immunoassays were evaluated for precision, accuracy, and specificity. Only 1 assay initially reached the requisite standard: Mercodia Equine Insulin Enzyme-linked Immunosorbent assay (ELISA). Plasma matrix interferences were identified when the provided assay buffer was used with the Siemens Count-a-Coat Insulin radioimmunoassay (RIA) but not when charcoal-stripped equine plasma was used as the diluent. This modified RIA and the Mercodia Equine Insulin ELISA were evaluated further by directly examining accuracy by comparing their results for 18 equine plasma samples with values obtained using liquid chromatography and high-resolution/high-accuracy mass spectrometry (LC-MS). Compared with LC-MS measurements, the modified Siemens Insulin RIA rendered a moderate Lin's concordance coefficient (ρ(c)) of 0.41, whereas the Mercodia Equine Insulin ELISA rendered a very poor ρ(c) of 0.06. This suggests that the Siemens Insulin RIA is appropriate to use for routine evaluations when LC-MS is not available.
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Response to Letter to the Editor regarding “Rapid determination of urinary di(2-ethylhexyl) phthalate metabolites based on liquid chromatography/tandem mass spectrometry as a marker for blood transfusion in sports drug testing”. Anal Bioanal Chem 2011. [DOI: 10.1007/s00216-011-4841-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Investigation of the in vitro metabolism of the emerging drug candidate S107 for doping-preventive purposes. JOURNAL OF MASS SPECTROMETRY : JMS 2011; 46:112-130. [PMID: 21254313 DOI: 10.1002/jms.1878] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 11/30/2010] [Indexed: 05/30/2023]
Abstract
The metabolic fate of the emerging drug candidate S107, possessing the potential for misuse as performance-enhancing agent in sports, was investigated by in vitro phase I and II experiments with human microsomal and S9 liver enzymes. The metabolites were identified by liquid chromatography-mass spectrometry with electrospray ionisation in positive mode (LC-ESI-MS/MS). Their collision-induced dissociation behaviour was studied by high-resolution/high accuracy Orbitrap MS(n) analysis, supported by stable isotope labelling, H/D-exchange experiments and density functional theory calculations. Monooxygenation accounted for the main phase I metabolic transformation due to N- and S-oxidation of the 1,4-benzothiazepine core, as substantiated by chemical synthesis, selective reduction methods and characteristic APCI in source fragmentation behaviour of the metabolites. Another dominant metabolic pathway was demethylation, yielding the N- and O-demethylated metabolite, respectively. The latter was further conjugated by glucuronidation as well as sulfonation in subsequent phase II metabolic reactions, whereas the N-demethylated metabolite was not amenable to conjugation. The active drug molecule itself was converted to two glucuronic acid conjugates, which are proposed to consist of two quaternary S107-N(+)-glucuronide isomers. All glucuronides were susceptible to enzymatic hydrolysis with β-glucuronidase (Escherichia coli). A comprehensive LC-ESI-MS(/MS)-based detection method for urine was developed and its fitness for purpose was assessed. The assay can serve as a potential screening and/or confirmation method for S107 in clinical drug testing and doping control analysis in the future.
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Rapid determination of urinary di(2-ethylhexyl) phthalate metabolites based on liquid chromatography/tandem mass spectrometry as a marker for blood transfusion in sports drug testing. Anal Bioanal Chem 2010; 401:517-28. [DOI: 10.1007/s00216-010-4589-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 11/30/2010] [Accepted: 12/08/2010] [Indexed: 02/08/2023]
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Terbutaline sulfoconjugate: characterization and urinary excretion monitored by LC/ESI-MS/MS. Drug Test Anal 2009; 1:568-75. [DOI: 10.1002/dta.84] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Analysis of Major Isoforms of Human Growth Hormone before and after Intensive Physical Exercise. Bull Exp Biol Med 2009; 146:466-9. [DOI: 10.1007/s10517-009-0335-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Analysis of Confiscated Black Market Drugs Using Chromatographic and Mass Spectrometric Approaches. J Anal Toxicol 2008; 32:232-40. [DOI: 10.1093/jat/32.3.232] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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The prohormone 19-norandrostenedione displays selective androgen receptor modulator (SARM) like properties after subcutaneous administration. Toxicol Lett 2008; 177:198-204. [DOI: 10.1016/j.toxlet.2008.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Revised: 01/20/2008] [Accepted: 01/21/2008] [Indexed: 11/26/2022]
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Long-term engraftment following transplantation of pig pancreatic primordia into non-immunosuppressed diabetic rhesus macaques. Xenotransplantation 2008; 14:591-602. [PMID: 17991147 DOI: 10.1111/j.1399-3089.2007.00429.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Transplantation therapy for human diabetes is limited by a shortage of donor organs, and transplant function diminished over time by cell death and limited potential for expansion of beta cells in pancreas or islets. Outcomes are complicated by immunosuppression. A way to overcome supply and expansion problems is to xenotransplant embryonic tissue. Previously, we have shown that beta cells originating from embryonic day (E) 28 (E28) pig pancreatic primordia transplanted into the mesentery of streptozotocin (STZ)-diabetic (type 1) Lewis rats or Zucker Diabetic Fatty (ZDF) diabetic (type 2) rats engraft and normalize glucose tolerance without the need for host immune-suppression. METHODS In this study, we transplant E28 pig pancreatic primordia in the mesentery of STZ-diabetic rhesus macaques. RESULTS Long-term engraftment of pig beta cells within liver, pancreas and mesenteric lymph nodes post-transplantation of E28 pig pancreatic primordia into STZ-diabetic rhesus macaques is demonstrated by electron microscopy, positive immune-histochemistry for insulin, and positive RT-PCR and in situ hybridization for porcine proinsulin mRNA. Insulin requirements were reduced in one macaque followed over 22 months post-transplantation and porcine insulin detected in plasma using sequential affinity chromatography, HPLC and mass spectrometry. Of potential importance for application of this transplantation technology to treatment of diabetes in humans and confirmatory of our previous findings in Lewis and ZDF rats, no host immunosuppression is required. CONCLUSIONS Under selected circumstances, pancreatic primordia elicit a muted immune response relative to more differentiated tissue, such that engraftment occurs in non-immunosuppressed hosts. Our findings that pig pancreatic primordia engraft long-term in non-immunosuppressed STZ-diabetic rhesus macaques establishes the potential for their use in human diabetics.
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Discrimination of Recombinant and Endogenous Urinary Erythropoietin by Calculating Relative Mobility Values from SDS Gels. Int J Sports Med 2008; 29:1-6. [DOI: 10.1055/s-2007-989369] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
The aim of the present study was to improve and validate a flow cytometric method for the detection of homologous blood transfusion in doping control analysis. A panel of eight different primary antibodies and two different phycoerythrin-conjugated secondary antibodies was used for the detection of different blood populations. The flow cytometer used in this study was the BD FACSArray instrument. Mixed red blood cell populations were prepared from phenotype known donors. Linearity, specificity, recovery, precision, robustness and interday-precision were tested for every primary antibody used in the presented assay. The technique of signal amplification was utilized for an improved separation of antigens with weak or heterozygous expression to improve the interpretation of histograms. The resulting method allowed to clearly identify mixed red blood cell populations in homologous blood transfusion samples containing 0.3 - 2.0 % of donor blood.
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Abstract
Urine manipulation in sports drug testing has become a serious problem for doping control laboratories, and recent scandals in elite endurance sports have revealed the problem of urine manipulation presumably using proteases, which will impede the detection of drugs such as erythropoietin (EPO) or other peptide hormones. Using commonly accepted analytical strategies, a protocol was developed enabling the determination of elevated protease activities in doping control specimens followed by the visualization of protein degradation and identification of proteases such as chymotrypsin, trypsin and papain. Therefore, protease detection kits based on fluorescein isothiocyanate-labeled casein were employed, and protease concentrations greater than 15 microg/mL of urine entailed subsequent 1-dimensional gel electrophoretic visualization of urinary proteins. The presence of 20 microg of proteases per mL of urine caused a complete degradation of proteins usually observed in urinary matrices ("trace of burning"), while respective proteases were still detected in spiked urine samples after 10 days of storage at + 4 and - 20 degrees C. Identification of target proteases at respective molecular weights was accomplished using bottom-up sequencing approaches based on in-gel digestion of separated enzymes followed by capillary liquid chromatography--Orbitrap tandem mass spectrometry.
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Abstract
Preventive doping research includes the development of methods for the detection of new or emerging drugs to be implemented in routine screening analysis. Candidates with great potential for misuse in elite sports include selective androgen receptor modulators, growth hormone secretagogues, hypoxia-inducible factor stabilizers and erythropoietin mimetics.
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Characterisation of the pharmacological profile of desoxymethyltestosterone (Madol), a steroid misused for doping. Toxicol Lett 2007; 169:64-71. [PMID: 17254722 DOI: 10.1016/j.toxlet.2006.12.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Revised: 12/13/2006] [Accepted: 12/14/2006] [Indexed: 11/29/2022]
Abstract
Desoxymethyltestosterone (DMT), also known as Madol, is a steroid recently identified to be misused as a doping agent. Since, the knowledge of functions of this substance is rather limited, it was our aim to characterise the pharmacological profile of DMT and to identify potential adverse side effects. DMT was synthesised, its purity was confirmed and its biological activity was tested. The potency of Madol (DMT) to transactivate androgen receptor (AR) dependent reporter gene expression was two times lower as compared to dihydrotestosterone (DHT). Receptor binding tests demonstrate that DMT binds with high selectivity to the AR, binding to the progesterone receptor (PR) was low. In vivo experiments in orchiectomised rats demonstrated that treatment with DMT resulted only in a stimulation of the weight of the levator ani muscle; the prostate and seminal vesicle weights remained unaffected. Like testosterone, administration of DMT resulted in a stimulation of IGF-1 and myostatin mRNA expression in the gastrocnemius muscle. In the prostate proliferation was stimulated by TP (testosteronepropionate), but remained unaffected by DMT. Remarkably, treatment with DMT, in contrast to TP, resulted in a significant increase of the heart weight. In the liver, DMT slightly stimulates the expression of the tyrosine aminotransferase gene (TAT). Our results demonstrate that DMT is a potent AR agonist with an anabolic activity. Besides the levator ani weight, DMT also modulates the gene expression in the musculus gastrocnemius. The observed stimulation of TAT expression in the liver and the significant increase of the heart weight after DMT treatment can be taken as an indication for side effects. Summarizing these data it is obvious that DMT is a powerful anabolic steroid with selective androgen receptor modulators (SARM) like properties and some indications for toxic side effects. Therefore, there is a need for a strict control of a possible misuse.
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Abstract
The Federation Equestre Internationale has permitted the use of altrenogest in mares for the control of oestrus. However, altrenogest is also suspicious to misuse in competition horses for its potential anabolic effects and suppression of typical male behaviour, and thus is a controlled drug. To investigate the pharmacokinetics of altrenogest in horses we conducted an elimination study. Five oral doses of 44 mug/kg altrenogest were administered to 10 horses at a dose interval of 24 h. Following administration blood and urine samples were collected at appropriate intervals. Altrenogest concentrations were measured by liquid chromatography-tandem mass spectrometry. The plasma levels of altrenogest reached maximal concentrations of 23-75 ng/mL. Baseline values were achieved within 3 days after the final administration. Urine peak concentrations of total altrenogest ranged from 823 to 3895 ng/mL. Twelve days after the final administration concentrations were below the limit of detection (ca 2 ng/mL).
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36
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Quantitative Determination of Adrenaline and Noradrenaline in Urine Using Liquid Chromatography-Tandem Mass Spectrometry. Chromatographia 2006. [DOI: 10.1365/s10337-006-0067-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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37
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Detection of Stanozolol and Its Major Metabolites in Human Urine by Liquid Chromatography-Tandem Mass Spectrometry. Chromatographia 2006. [DOI: 10.1365/s10337-006-0043-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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38
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Tetrahydrogestrinone is a potent but unselective binding steroid and affects glucocorticoid signalling in the liver. Toxicol Lett 2006; 164:16-23. [PMID: 16356667 DOI: 10.1016/j.toxlet.2005.11.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Revised: 11/11/2005] [Accepted: 11/11/2005] [Indexed: 10/25/2022]
Abstract
Tetrahydrogestrinone (THG) is a steroid recently identified to be misused as doping agent. However, the knowledge on functions of this substance in humans or animal models is rather limited. Therefore, it was our aim to further characterize the pharmacological profile of THG and identify potential adverse side effects. THG was synthesized, the purity was confirmed and its biological activity was tested. The potency of THG to transactivate AR dependent reporter gene expression was two orders of magnitude lower compared to dihydrotestosterone. THG binds with high affinity but unselective to the androgen (AR), progesterone (PR), glucocorticoid (GR) and mineralocorticoid (MR) receptor. Treatment of orchiectomised rats with THG resulted in a stimulation of prostate, seminal vesicle and levator ani muscle, indicating androgenic and anabolic properties. In the liver THG, in contrast to testosteronepropionate (TP), down regulates the expression of the GR dependent tyrosine aminotransferase gene (TAT). In summary, our results demonstrate that THG is not a specific AR agonist. THG exhibits a high binding affinity to all tested steroid hormone receptors and binds with highest affinity to the GR. Our in vivo data are indicative of an anabolic and androgenic potency of THG, but the repression of TAT demonstrates that THG also interferes with the glucocorticoid hormone system. Therefore, it is conceivable that an intake will result in adverse side effects.
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17beta-hydroxy-5alpha-androst-1-en-3-one (1-testosterone) is a potent androgen with anabolic properties. Toxicol Lett 2006; 165:149-55. [PMID: 16621347 DOI: 10.1016/j.toxlet.2006.03.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Revised: 03/07/2006] [Accepted: 03/10/2006] [Indexed: 11/30/2022]
Abstract
Since the begining of the year 2005, the use of steroid precursors (prohormones) is illegal in the United States; nevertheless, there is still an enormous abuse of such substances. One of the most frequently misused steroids, often declared to be a prohormone, is 1-testosterone (17beta-hydroxy-5alpha-androst-1-en-3-one, 1-Testo). In this study, we have characterised molecular mechanisms of its action, determined its tissue specific androgenic and anabolic potency and investigated potential adverse effects. 1-Testo binds highly selective to the androgen receptor (AR) and has a high potency to stimulate AR dependent transactivation. In vivo an equimolar dose of 1-Testo has the same potency to stimulate the growth of the prostate, the seminal vesicles and the androgen sensitive levator ani muscle as the reference compound testosterone propionate (TP). Administration of 1-Testo, in contrast to TP, results in a significant increase of liver weight. Our results demonstrate that 1-Testo, even without being metabolised, is a very potent androgen. It binds selectively to the AR and transactivates AR dependent reporter genes. In vivo it has a high androgenic and anabolic potency and increases liver weight. In summary 1-Testo can be characterised as a typical anabolic steroid. It has to be assumed that consumption of this substance is associated with adverse side effects typical for this class of compounds. Therefore, a strict control of its ban is essential.
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Quantification of Clenbuterol in Human Plasma and Urine by Liquid Chromatography-Tandem Mass Spectrometry. Chromatographia 2005. [DOI: 10.1365/s10337-005-0651-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Identification of the aromatase inhibitor letrozole in urine by gas chromatography/mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:3689-93. [PMID: 16299697 DOI: 10.1002/rcm.2239] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Letrozole (1-(bis-(4-cyanophenyl)methyl)-1,2,4-triazole) is used therapeutically as a non-steroidal aromatase inhibitor (Femara) to treat hormone-sensitive breast cancer in postmenopausal women. For doping purposes it may be used to counteract the adverse effects of an extensive abuse of anabolic androgenic steroids (gynaecomastia) and to increase the testosterone concentration by stimulation of the testosterone biosynthesis. The use of aromatase inhibitors has been prohibited by IOC/WADA regulations for male and female athletes since September 2001 and January 2005, respectively. Spot urine samples from women suffering from metastatic breast cancer and being treated with letrozole were collected and analysed to develop/optimise the detection system for metabolites of letrozole to allow the identification of athletes who do not comply with the internationally prohibited use of this cancer drug. The assay was based on gas chromatography/mass spectrometry (GC/MS) and the main metabolite of letrozole (bis-4-cyanophenylmethanol) was identified by comparison of its mass spectrum and retention time with that of a bis-4-cyanophenylmethanol reference. The full-scan spectrum, diagnostic ions and a validation of the method for the analysis of bis-4-cyanophenylmethanol are presented.
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High speed determination of beta-receptor blocking agents in human urine by liquid chromatography/tandem mass spectrometry. Biomed Chromatogr 2001; 15:393-402. [PMID: 11559924 DOI: 10.1002/bmc.87] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Beta-receptor blocking agents are present on the international market in a huge variety. The International Olympic Committee prohibits the use of these drugs in several sport sections and doping control laboratories analyse urine samples of high-performance athletes with different techniques. Therefore, fast and reliable methods are required to enable a sensitive detection of many drugs and a high throughput of samples. In the present study a screening procedure is described using high speed liquid chromatography and multiple reaction monitoring to identify 32 beta-receptor blocking agents extracted from human urine. Urine specimens (blank urine samples, spiked urine samples and specimens of excretion studies) were hydrolysed, extracted and analysed within 7 min. Quasi-molecular ions (M(+) + H) of the beta-blockers are generated by means of an atmospheric pressure chemical ionization interface followed by collision-induced dissociation in a triple quadrupole mass spectrometer and subsequent detection of daughter ions. Proposals for the origin of common and individual secondary ions are presented.
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Mass spectrometry of steroid glucuronide conjugates. II-Electron impact fragmentation of 3-keto-4-en- and 3-keto-5alpha-steroid-17-O-beta glucuronides and 5alpha-steroid-3alpha,17beta-diol 3- and 17-glucuronides. JOURNAL OF MASS SPECTROMETRY : JMS 2001; 36:998-1012. [PMID: 11599078 DOI: 10.1002/jms.203] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The steroid glucuronide conjugates of 16,16,17-d(3)-testosterone, epitestosterone, nandrolone (19-nortestosterone), 16,16,17-d(3)-nortestosterone, methyltestosterone, metenolone, mesterolone, 5alpha-androstane-3alpha,17beta-diol, 2,2,3,4,4-d(5)-5alpha-androstane-3alpha,17beta-diol, 19-nor-5alpha-androstane-3alpha,17beta-diol, 2,2,4,4-d(4)-19-nor-5alpha-androstane-3alpha,17beta-diol and 1alpha-methyl-5alpha-androstane-3alpha/beta,17beta-diol were synthesized by means of the Koenigs-Knorr reaction. Selective 3- or 17-O-conjugation of bis-hydroxylated steroids was performed either by glucuronidation of the corresponding steroid ketole and subsequent reduction of the keto group or via a four-step synthesis starting from a mono-hydroxylated steroid including (a) protection of the hydroxy group, (b) reduction of the keto group, (c) conjugation reaction and (d) removal of protecting groups. The mass spectra and fragmentation patterns of all glucuronide conjugates were compared with those of the commercially available testosterone glucuronide and their characterization was performed by gas chromatography/mass spectrometry and nuclear magnetic resonance spectroscopy. For mass spectrometry the substances were derivatized to methyl esters followed by trimethylsilylation of hydroxy groups and to pertrimethylsilylated products using labelled and unlabelled trimethylsilylating agents. The resulting electron ionization mass spectra obtained by GC/MS quadrupole and ion trap instruments, full scan and selected reaction monitoring experiments are discussed, common and individual fragment ions are described and their origins are proposed.
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Mass spectrometry of steroid glucuronide conjugates. I. Electron impact fragmentation of 5alpha-/5beta-androstan-3alpha-ol-17-one glucuronides, 5alpha-estran-3alpha-ol-17-one glucuronide and deuterium-labelled analogues. JOURNAL OF MASS SPECTROMETRY : JMS 2001; 36:159-168. [PMID: 11288198 DOI: 10.1002/jms.117] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Owing to the developments of analytical instruments and interfaces (e.g. coupling high-performance liquid chromatography to mass spectrometry), there has been increased interest in new reference materials, for example in doping analysis with steroid glucuronide conjugates. The synthesized reference material has to pass several characterization steps including the use of gas chromatography/mass spectrometry (GC/MS) for its structure confirmation. In the present study, the fragmentation and mass spectrometric behaviour of several steroid glucuronide conjugates of endogenous and anabolic steroids after derivatization to pertrimethylsilylated products and to methyl ester pertrimethylsilylated products were investigated using GC/MS ion trap and GC/MS quadrupole instruments. The mass spectra of the derivatives of androsterone glucuronide, d5-androsterone glucuronide, epiandrosterone glucuronide, etiocholanolone glucuronide, 11beta-hydroxy etiocholanolone glucuronide, 19-norandrosterone glucuronide, d4-19-norandrosterone glucuronide and 1alpha-methyl-5alpha-androstan-3alpha-ol-17-one glucuronide are presented and the origin of typical fragment ions of the glycosidic and steroidal moieties is proposed, based on different derivatization techniques including derivatization with d18-bistrimethylsilylacetamide, methyl ester and trimethylsilyl ester derivatization and selected reaction monitoring. Typical fragmentation patterns which are related to the steroid structure are discussed.
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Detection of the plasma volume expander hydroxyethyl starch in human urine. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 744:345-50. [PMID: 10993523 DOI: 10.1016/s0378-4347(00)00251-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The plasma volume expander hydroxyethyl starch (HES) is usually administered in cases of hypovolaemic shocks but in 1998 the press reported its misuse in endurance sports. Since January 2000, it has been put on the list of prohibited substances of the International Olympic Committee (IOC) and its misuse is to ban by doping controls. Therefore, a rapid method enabling the screening for HES in human urine was developed which can be easily adopted by IOC laboratories to analyse routine urine samples for this remedy. Excretion study urine samples obtained from patients treated with HES, blank urine specimen and reference standards, were hydrolysed with hydrochloric acid and without any further purification of the resulting monosaccharides their per-timethylsilylated derivatives were performed. By means of gas chromatography-mass spectrometry the products were separated and the alpha- and beta-isomers of glucose, 2-, 3- and 6-hydroxyethyl glucose derivatives were identified. Typical ion traces of 2- and 3-substituted glucose (m/z 248, m/z 261 and m/z 235, m/z 248, respectively) support the fast determination of the substances whose electron impact mass spectra are presented and discussed.
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47
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Abstract
The degradation and derivatization of hydroxyethyl starch to partially methylated alditol acetates (PMAAs) allows its detection by gas chromatography/mass spectrometry. The derivatization was performed by permethylation of the carbohydrate, hydrolysis of the permethylated polysaccharide, reduction of the resulting monosaccharides to alditoles and finally acetylation. A close similarity in the fragmentation of the PMAAs obtained was observed in both electron ionization (EI) and chemical ionization (CI) mass spectra owing to the comparable structures of the derivatives. CI measurements permitted the recognition of introduced hydroxyethyl groups in the glucose residues by detection of [M(+)+1]-60 signals. Investigations concerning the EI fragmentation schemes allowed secure determinations of monohydroxyethyl monosaccharides and differentiations between the possible positions (C-2, C-3 and C-6) of the substituted hydroxyethyl groups. Proposed generations of the main fragment ions are presented.
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