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1.
Molecules ; 26(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802606

RESUMEN

Metandienone and methyltestosterone are orally active anabolic-androgenic steroids with a 17α-methyl structure that are prohibited in sports but are frequently detected in anti-doping analysis. Following the previously reported detection of long-term metabolites with a 17ξ-hydroxymethyl-17ξ-methyl-18-nor-5ξ-androst-13-en-3ξ-ol structure in the chlorinated metandienone analog dehydrochloromethyltestosterone ("oral turinabol"), in this study we investigated the formation of similar metabolites of metandienone and 17α-methyltestosterone with a rearranged D-ring and a fully reduced A-ring. Using a semi-targeted approach including the synthesis of reference compounds, two diastereomeric substances, viz. 17α-hydroxymethyl-17ß-methyl-18-nor-5ß-androst-13-en-3α-ol and its 5α-analog, were identified following an administration of methyltestosterone. In post-administration urines of metandienone, only the 5ß-metabolite was detected. Additionally, 3α,5ß-tetrahydro-epi-methyltestosterone was identified in the urines of both administrations besides the classical metabolites included in the screening procedures. Besides their applicability for anti-doping analysis, the results provide new insights into the metabolism of 17α-methyl steroids with respect to the order of reductions in the A-ring, the participation of different enzymes, and alterations to the D-ring.


Asunto(s)
Anabolizantes/metabolismo , Anabolizantes/orina , Metandrostenolona/metabolismo , Metandrostenolona/orina , Metiltestosterona/metabolismo , Metiltestosterona/orina , Anabolizantes/química , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Metandrostenolona/química , Metiltestosterona/química , Persona de Mediana Edad , Estándares de Referencia , Espectrometría de Masas en Tándem
2.
J Sep Sci ; 36(24): 3903-10, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24151099

RESUMEN

An online system that can perform dynamic microextraction, on-coating derivatization and desorption, and subsequent GC-MS analysis with a large-volume injection was developed. A derivatization cell as the conjunction of the online system was developed for the online extraction and derivatization. To evaluate the feasibility of the online system, methyltestosterone molecularly imprinted polymer filaments (MIPFs) were prepared for the selective online extraction of five androgenic steroids, namely, methyltestosterone, testosterone, epitestosterone, nandrolone, and metandienone. Under the optimized conditions, the detection limits of testosterone and epitestosterone were 0.09 and 0.12 µg/L, respectively, which were under the minimum required performance limits between 2 and 10 µg/L from the World Anti-Doping Agency. The detection limits of the other three androgenic steroids were varied from 0.04 to 0.18 µg/L. Finally, the MIPFs-GC-MS method was applied for the determination of androgenic steroids in urine, and satisfactory recovery (78.0-96.9%) and reproducibility (3.2-8.9%) were obtained. The proposed online coupling system offers an attractive alternative for hyphenation to GC instruments and could also be extended to other adsorptive materials.


Asunto(s)
Andrógenos/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Impresión Molecular , Polímeros/química , Epitestosterona/orina , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Humanos , Masculino , Metandrostenolona/orina , Metiltestosterona/orina , Nandrolona/orina , Polímeros/síntesis química , Testosterona/orina
3.
Arch Toxicol ; 85(4): 285-92, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20924560

RESUMEN

The routinely used analytical method for detecting the abuse of anabolic steroids only allows the detection of molecules with known analytical properties. In our supplementary approach to structure-independent detection, substances are identified by their biological activity. In the present study, urines excreted after oral methyltestosterone (MT) administration were analyzed by a yeast androgen screen (YAS). The aim was to trace the excretion of MT or its metabolites in human urine samples and to compare the results with those from the established analytical method. MT and its two major metabolites were tested as pure compounds in the YAS. In a second step, the ability of the YAS to detect MT and its metabolites in urine samples was analyzed. For this purpose, a human volunteer ingested of a single dose of 5 mg methyltestosterone. Urine samples were collected after different time intervals (0-307 h) and were analyzed in the YAS and in parallel by GC/MS. Whereas the YAS was able to trace MT in urine samples at least for 14 days, the detection limits of the GC/MS method allowed follow-up until day six. In conclusion, our results demonstrate that the yeast reporter gene system could detect the activity of anabolic steroids like methyltestosterone with high sensitivity even in urine. Furthermore, the YAS was able to detect MT abuse for a longer period of time than classical GC/MS. Obviously, the system responds to long-lasting metabolites yet unidentified. Therefore, the YAS can be a powerful (pre-) screening tool with the potential that to be used to identify persistent or late screening metabolites of anabolic steroids, which could be used for an enhancement of the sensitivity of GC/MS detection techniques.


Asunto(s)
Anabolizantes/farmacocinética , Metiltestosterona/farmacocinética , Saccharomyces cerevisiae/efectos de los fármacos , Detección de Abuso de Sustancias/métodos , Anabolizantes/orina , Bioensayo , Cromatografía de Gases y Espectrometría de Masas , Genes Reporteros , Humanos , Masculino , Metiltestosterona/análogos & derivados , Metiltestosterona/orina , Persona de Mediana Edad , Saccharomyces cerevisiae/fisiología , Detección de Abuso de Sustancias/estadística & datos numéricos , Espectrometría de Masas en Tándem , Factores de Tiempo , Activación Transcripcional/efectos de los fármacos
4.
Rapid Commun Mass Spectrom ; 24(7): 958-64, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20209666

RESUMEN

We examined the feasibility of capillary liquid chromatography/microchip atmospheric pressure photoionization tandem mass spectrometry (capLC/microAPPI-MS/MS) for the analysis of anabolic steroids in human urine. The urine samples were pretreated by enzymatic hydrolysis (with beta-glucuronidase from Helix pomatia), and the compounds were liquid-liquid extracted with diethyl ether. After separation the compounds were vaporized by microchip APPI, photoionized by a 10 eV krypton discharge lamp, and detected by selected reaction monitoring. The capLC/microAPPI-MS/MS method showed good sensitivity with detection limits at the level of 1.0 ng mL(-1), good linearity with correlation coefficients between 0.9954 and 0.9990, and good repeatability with relative standard deviations below 10%. These results demonstrate that microchip APPI combined with capLC/MS/MS provides a new potential method for analyzing non-polar and neutral compounds in biological samples.


Asunto(s)
Anabolizantes/orina , Electrocromatografía Capilar/métodos , Espectrometría de Masas/métodos , Procedimientos Analíticos en Microchip/métodos , Esteroides/orina , Humanos , Modelos Lineales , Metandrostenolona/orina , Metiltestosterona/orina , Nandrolona/orina , Nebulizadores y Vaporizadores , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , beta-Glucosidasa/química , beta-Glucosidasa/metabolismo
5.
J Pharm Biomed Anal ; 45(1): 125-133, 2007 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-17709226

RESUMEN

Anabolic steroids with the 17alpha-methyl,17beta-hydroxyl group, which were developed as oral formulations for therapeutic purposes, have been abused in the field of human sports. These anabolic steroids are also used to enhance racing performance in racehorses. In humans, structurally related 17alpha-methyltestosterone (MTS) and mestanolone (MSL), which are anabolic steroids with the 17alpha-methyl,17beta-hydroxyl group, have metabolites in common. The purpose of this study was to determine metabolites common to these two steroids in horses, which may serve as readily available screening targets for the doping test of these steroids in racehorses. Urine sample collected after administering MTS and MSL to horses was treated to obtain unconjugated steroid, glucuronide, and sulfate fractions. The fractions were subjected to gas chromatography/mass spectrometry (GC/MS), and 17alpha-methyl-5alpha-androstan-3beta,17beta-diol, 17alpha-hydroxymethyl-5alpha-androstan-3beta,17beta-diol, 17alpha-methyl-5alpha-androstan-3beta,16beta,17beta-triol, and 17alpha-methyl-5alpha-androstan-3beta,16alpha,17beta-triol were detected as the common metabolites by comparison with synthesized reference standards. The urinary concentrations of these metabolites after dosing were determined by GC/MS. 17Alpha-methyl-5alpha-androstan-3beta,16beta,17beta-triol was mainly detected in the sulfate fractions of urine samples after administration. This compound was consistently detected for the longest time in the urine samples after dosing with both steroids. The results suggest that 17alpha-methyl-5alpha-androstan-3beta,16beta,17beta-triol is a very useful screening target for the doping test of MTS and MSL in racehorses.


Asunto(s)
Anabolizantes , Dihidrotestosterona/análogos & derivados , Caballos/orina , Metiltestosterona , Anabolizantes/metabolismo , Anabolizantes/orina , Animales , Calibración , Dihidrotestosterona/metabolismo , Dihidrotestosterona/orina , Cromatografía de Gases y Espectrometría de Masas , Metiltestosterona/metabolismo , Metiltestosterona/orina , Estructura Molecular , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
J Chromatogr A ; 1131(1-2): 267-74, 2006 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-16949594

RESUMEN

Separation of anabolic and androgenic steroids by micellar electrokinetic chromatography (MEKC) has been little studied. Simultaneous separation of the endogenous alpha-epimers testosterone and epitestosterone has not been achieved with any electroseparation technique. Here, a partial filling micellar electrokinetic chromatographic (PF-MEKC) method is described for the analysis of three endogenous steroid hormones (androstenedione, testosterone, epitestosterone) and two synthetic anabolic steroids (fluoxymesterone, methyltestosterone). The resolution efficiency of single-isomer sulphated gamma-cyclodextrins and the surfactants sodium dodecyl sulphate and sodium taurocholate was exploited. The method is based on the sequential introduction of short plugs of two different pseudostationary phases into the capillary. The separation was completed in less than 10 min. The method can be used in quantitative analysis. Linear correlation was obtained between concentration and peak area of 0.996 or better. The repeatability (RSD) of the compound peak areas ranged from 3.6% (methyltestosterone) to 6.2% (androstenedione). Limits of detection were between 73 microg/L (testosterone) and 160 microg/L (fluoxymesterone). As a demonstration of the method, androstenedione, testosterone and epitestosterone were determined in a spiked urine sample.


Asunto(s)
Andrógenos/análisis , Cromatografía Capilar Electrocinética Micelar/métodos , Testosterona/análisis , Andrógenos/química , Andrógenos/orina , Androstenodiona/análisis , Androstenodiona/química , Androstenodiona/orina , Electroforesis Capilar/métodos , Epitestosterona/análisis , Epitestosterona/química , Epitestosterona/orina , Humanos , Masculino , Metiltestosterona/análisis , Metiltestosterona/química , Metiltestosterona/orina , Estructura Molecular , Reproducibilidad de los Resultados , Testosterona/química , Testosterona/orina
7.
J Steroid Biochem Mol Biol ; 42(5): 533-46, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1616883

RESUMEN

The epimerization and dehydration reactions of the 17 beta-hydroxy group of anabolic 17 beta-hydroxy-17 alpha-methyl steroids have been investigated using the pyridinium salts of 17 beta-sulfate derivatives of methandienone 1, methyltestosterone 4, oxandrolone 7, mestanolone 10 and stanozolol 11 as model compounds. Rearrangement of the sulfate conjugates in buffered urine (pH 5.2) afforded the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes in a ratio of 0.8:1. These data indicated that both epimerization and dehydration of the 17 beta-sulfate derivatives were not dependent upon the respective chemical features of the steroids studied, but were instead inherent to the chemistry of the tertiary 17 beta-hydroxy group of these steroids. Interestingly, in vivo studies carried out with human male volunteers showed that only methandienone 1, methyltestosterone 4 and oxandrolone 7 yielded the corresponding 17-epimers 2, 5 and 8 and the 18-nor-17,17-dimethyl-13(14)-enes 3, 6 and 9 in ratios of 0.5:1, 2:1 and 2.7:1, respectively. No trace of the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of mestanolone 10 and stanozolol 11 was detected in urine samples collected after administration of these steroids. These data suggested that the in vivo formation of the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of 17 beta-hydroxy-17 alpha-methyl steroids is also dependent upon phase I and phase II metabolic reactions other than sulfation of the tertiary 17 beta-hydroxyl group, which are probably modulated by the respective chemical features of the steroidal substrates. The data reported in this study demonstrate that the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes are not artifacts resulting from the acidic or microbial degradation of the parent steroids in the gut as previously suggested by other authors, but arise from the rearrangement of their 17 beta-sulfate derivatives. Unchanged oxandrolone 7 was solely detected in the unconjugated steroid fraction whereas unchanged steroids 1, 4 and 11 were recovered from the glucuronide fraction. These data are indirect evidences suggesting that the glucuronide conjugates of compounds 1 and 4 are probably enol glucuronides and that of compound 11 is excreted in urine as a N-glucuronide involving its pyrazole moiety. The urinary excretion profiles of the epimeric and 18-nor-17,17-dimethyl-13(14)-ene steroids are presented and discussed on the basis of their structural features.


Asunto(s)
Anabolizantes/metabolismo , Hidroxiesteroides/metabolismo , Adulto , Anabolizantes/sangre , Anabolizantes/química , Anabolizantes/orina , Dihidrotestosterona/análogos & derivados , Dihidrotestosterona/metabolismo , Dihidrotestosterona/orina , Cromatografía de Gases y Espectrometría de Masas , Glucuronatos/metabolismo , Humanos , Hidroxiesteroides/sangre , Cinética , Masculino , Espectrometría de Masas , Metandrostenolona/metabolismo , Metandrostenolona/orina , Metiltestosterona/metabolismo , Metiltestosterona/orina , Oxandrolona/metabolismo , Oxandrolona/orina , Estanozolol/metabolismo , Estanozolol/orina , Azufre/metabolismo
8.
Steroids ; 37(6): 593-600, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7292534

RESUMEN

A radioimmunoassay determination method was developed for 17-epimethyltestosterone (17 alpha-hydroxy-17-methyl-4-androstein-3-one). Excretion of metabolites during and after methandienone (17 beta-hydroxy-17-methyl-1,4-androstadien-3-one) administration was followed in human urine samples by RIA tests for methandienone and 17-epimethyltestosterone. While alternating peaks were found in both measured excretion curves, their addition results in a normal curve showing a plateau between the 3rd and 6th day of the drug administration. Furthermore, due to the presence of higher amounts of epi-configurated metabolites, the new test has a higher effectiveness in the detection of the metabolites.


Asunto(s)
Metandrostenolona/orina , Metiltestosterona/orina , Animales , Reacciones Cruzadas , Masculino , Conejos , Radioinmunoensayo/métodos
9.
Yao Xue Xue Bao ; 28(12): 918-23, 1993.
Artículo en Zh | MEDLINE | ID: mdl-8030416

RESUMEN

The metabolites of calusterone (17 beta-OH-7 beta, 17 alpha-dimethyl-androst-4-ene-3-one) in man has been investigated by GC/MS. After oral administration, the parent compound and seven metabolites were detected in the conjugated fraction. The extraction and fractionation of these metabolites were achieved by using XAD-2 column. The sample was derivatized with MSTFA/TMSI before GC/MS analysis. The mass spectra of the metabolites are presented and the metabolic pathway was discussed.


Asunto(s)
Metiltestosterona/análogos & derivados , Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Metiltestosterona/metabolismo , Metiltestosterona/orina
10.
Yao Xue Xue Bao ; 24(3): 207-11, 1989.
Artículo en Zh | MEDLINE | ID: mdl-2816377

RESUMEN

A simple method for determining androgens and anabolic steroids in human urine by HPLC has been developed. The compounds studied are nandrolone, methandienone, testosterone, methyltestosterone, testosterone propionate and nandrolone phenylpropionate. The stationary phase used is C8 bonded silica. Isocratic elution was done with CH3OH-CH3CN-H2O (4:5:6) and programmed flow. Detection limit can be less than 1 ng at the wavelength of 254 nm. The standard curves for each steroid have been set using internal standard (progesterone) and peak height ratio. Linear relationship exists between the ratio and concentration for each steroid. High and stable recovery has been achieved using Sep-Pak C18 cartridges for urine sample clean-up. The operation of the method is simple. The enzymatic hydrolyzation of conjugated steroids in human urine has also been investigated.


Asunto(s)
Anabolizantes/orina , Andrógenos/orina , Cromatografía Líquida de Alta Presión , Humanos , Metandrostenolona/orina , Metiltestosterona/orina , Nandrolona/orina , Testosterona/orina
11.
J Chromatogr A ; 1312: 111-7, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-24041507

RESUMEN

A gas chromatography-microchip atmospheric pressure photoionization-tandem mass spectrometry (GC-µAPPI-MS/MS) method was developed for the analysis of anabolic androgenic steroids in urine as their trimethylsilyl derivatives. The method utilizes a heated nebulizer microchip in atmospheric pressure photoionization mode (µAPPI) with chlorobenzene as dopant, which provides high ionization efficiency by producing abundant radical cations with minimal fragmentation. The performance of GC-µAPPI-MS/MS was evaluated with respect to repeatability, linearity, linear range, and limit of detection (LOD). The results confirmed the potential of the method for doping control analysis of anabolic steroids. Repeatability (RSD<10%), linearity (R(2)≥0.996) and sensitivity (LODs 0.05-0.1ng/mL) were acceptable. Quantitative performance of the method was tested and compared with that of conventional GC-electron ionization-MS, and the results were in good agreement.


Asunto(s)
Anabolizantes/orina , Clorobencenos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Anabolizantes/química , Andrógenos/química , Andrógenos/orina , Humanos , Límite de Detección , Modelos Lineales , Metiltestosterona/química , Metiltestosterona/orina , Modelos Moleculares , Nandrolona/química , Nandrolona/orina , Procesos Fotoquímicos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
12.
Steroids ; 78(1): 44-52, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23127819

RESUMEN

Methyltestosterone (MT) is one of the most frequently detected anabolic androgenic steroids in doping control analysis. MT misuse is commonly detected by the identification of its two main metabolites excreted as glucuronide conjugates, 17α-methyl-5α-androstan-3α,17ß-diol and 17α-methyl-5ß-androstan-3α,17ß-diol. The detection of these metabolites is normally performed by gas chromatography-mass spectrometry, after previous hydrolysis with ß-glucuronidase enzymes, extraction and derivatization steps. The aim of the present work was to study the sulphate fraction of MT and to evaluate their potential to improve the detection of the misuse of the drug in sports. MT was administered to healthy volunteers and urine samples were collected up to 30days after administration. After an extraction with ethyl acetate, urine extracts were analysed by liquid chromatography tandem mass spectrometry using electrospray ionisation in negative mode by monitoring the transition m/z 385 to m/z 97. Three diol sulphate metabolites (S1, S2 and S3) were detected. Potential structures for these metabolites were proposed after solvolysis and mass spectrometric experiments: S1, 17α-methyl-5ß-androstan-3α,17ß-diol 3α-sulphate; S2, 17ß-methyl-5α-androstan-3α,17α-diol 3α-sulphate; and S3, 17ß-methyl-5ß-androstan-3α,17α-diol 3α-sulphate. Synthesis of reference compounds will be required in order to confirm the structures. The retrospectivity of these sulphate metabolites in the detection of MT misuse was compared with the obtained with previously described metabolites. Metabolite S2 was detected up to 21days after MT administration, improving between 2 and 3 times the retrospectivity of the detection compared to the last long-term metabolite of MT previously described, 17α-hydroxy-17ß-methylandrostan-4,6-dien-3-one.


Asunto(s)
Metiltestosterona/análogos & derivados , Metiltestosterona/orina , Sustancias para Mejorar el Rendimiento/orina , Sulfatos/orina , Acetatos/química , Adulto , Biomarcadores/orina , Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas , Humanos , Inactivación Metabólica , Extracción Líquido-Líquido , Masculino , Metiltestosterona/química , Metiltestosterona/farmacocinética , Persona de Mediana Edad , Peso Molecular , Sustancias para Mejorar el Rendimiento/química , Sustancias para Mejorar el Rendimiento/farmacocinética , Estándares de Referencia , Solventes/química , Espectrometría de Masa por Ionización de Electrospray/normas , Detección de Abuso de Sustancias/métodos , Sulfatos/química , Sulfatos/farmacocinética , Espectrometría de Masas en Tándem/normas , Urinálisis
13.
Anal Chim Acta ; 717: 85-91, 2012 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-22304819

RESUMEN

Within the framework of the German National Residue Control Plan a specific number of samples of animal origin have to be analysed for natural and synthetic steroids each year. As a measure of external quality control of the methods applied in routine analysis a proficiency test was carried out. To this end, in-house reference material containing incurred residues of 17α- and 17ß-nortestosterone and 17α- and 17ß-estradiol as well as fortified residues of 17α-methyltestosterone and 17α-trenbolone in bovine urine were produced. Before sending the proficiency test material to the participants, the homogeneity of all samples was tested and confirmed. Furthermore extensive short- and long-term stability studies were carried out. The statistical evaluation of the proficiency test was performed by applying robust statistics as described in standard DIN 38402. Based on the target value and standard deviation z-scores were calculated as standardised measure of the laboratory performance. The evaluation of the proficiency test showed that nine laboratories submitted quantitative results within the tolerance limits for all analytes. Taking into account the individual decision limits, there were no false negative results. In overall evaluation, 11 of 12 laboratories participated successfully.


Asunto(s)
Cromatografía Liquida/normas , Cromatografía de Gases y Espectrometría de Masas/normas , Esteroides/orina , Espectrometría de Masas en Tándem/normas , Animales , Bovinos , Estradiol/orina , Metiltestosterona/orina , Nandrolona/orina , Estándares de Referencia , Acetato de Trembolona/orina
14.
Se Pu ; 28(1): 49-53, 2010 Jan.
Artículo en Zh | MEDLINE | ID: mdl-20458920

RESUMEN

A new oral drug containing an unknown anabolic androgenic steroid (AAS) was studied. The principal constituent of the unknown anabolic hormone was studied by infrared spectrum (IR), nuclear magnetic resonance spectroscopy (1H NMR), ultraviolet spectroscopy (UV), and mass spectroscopy (MS). It was inferred to be methyl-1-testosterone (M1T, 17beta-hydroxy-17alpha-methyl-5alpha-androst-1-en-3-one) which was just added to the prohibited list in 2006. In addition, a monitoring, screening and confirmation of methyl-1-testosterone was established. The detection limit (S/N = 3) was 2 ng/mL, and the limit of quantification (S/N = 10) was 10 ng/mL. The relative standard deviation was 9.8% (n = 7) for the determination of pretreated urine sample with internal standard. This method was successfully applied in the identification of M1T positive urine. The excretion curve of M1T in human urine is described. It is a significant work for the discovery, determination and monitoring of the new AAS.


Asunto(s)
Anabolizantes/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Metiltestosterona/orina , Esteroides/análisis , Anabolizantes/metabolismo , Doping en los Deportes/prevención & control , Humanos , Metiltestosterona/química , Metiltestosterona/metabolismo , Estructura Molecular , Esteroides/orina
18.
Talanta ; 78(3): 1083-9, 2009 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-19269476

RESUMEN

A new solid phase microextraction (SPME) method coupled with gas chromatography-mass spectrometry (GC-MS) was developed for rapid determination of four anabolic steroids such as 3alpha-hydroxy-5alpha-androstane-17-one (HA), dihydrotestosterone (DHT), androstenedione (AD) and methyltestosterone (MT) in pig urine. SPME was used to extract the four anabolic compounds directly without derivatization. The optimum SPME sampling conditions were based on the home-made carbowax-divinylbenzene (CW-DVB) fiber coating during extraction at 40 degrees C for 50 min with 0.18 g/mL NaCl solution and 750 rpm stirring speed. The linear ranges of the proposed method were in the range of 8-640 pg/mL for HA and DHT and 16-510 pg/mL for AD and MT, respectively. The detection limits (S/N=3) were from 2 to 8 pg/mL for the four anabolic steroids. This SPME method provided very high enrichment factors for the four anabolic steroids, which were 1063-fold and 965-fold for HA and DHT at the concentration of 8 pg/mL and 207-fold and 451-fold for AD and MT at the concentration of 16 pg/mL, respectively. The recoveries ranged from 71.3 to 121%, and the RSDs were lower than 12.9%. The method was sensitive and reliable for determination of trace anabolic steroids in biological samples.


Asunto(s)
Anabolizantes/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Esteroides/orina , Androstenodiona/orina , Androsterona/orina , Animales , Dihidrotestosterona/orina , Metiltestosterona/orina , Microextracción en Fase Sólida , Sus scrofa
19.
Rapid Commun Mass Spectrom ; 23(5): 713-21, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19199316

RESUMEN

Gas chromatography/mass spectrometry and selective derivatisation techniques have been used to identify urinary metabolites of methyltestosterone following oral administration to the greyhound. Several metabolites were identified including reduced, mono-, di- and trihydroxylated steroids. The major metabolites observed were 17alpha-methyl-5beta-androstane-3alpha-17beta-diol, 17alpha-methyl-5beta-androstane-3alpha,16alpha,17beta-triol, and a further compound tentatively identified as 17alpha-methyl-5z-androstane-6z,17beta-triol. The most abundant of these was the 17alpha-methyl-5beta-androstane-3alpha,16alpha,17beta-triol. This metabolite was identified by comparison with a reference standard synthesised using a Grignard procedure and characterised using trimethylsilyl (TMS) and acetonide-TMS derivatisation techniques. There did not appear to be any evidence for 16beta-hydroxylation as a phase I metabolic transformation in the greyhound. However, significant quantities of 16alpha-hydroxy metabolites were detected. Selective enzymatic hydrolysis procedures indicated that the major metabolites identified were excreted as glucuronic acid conjugates. Metabolic transformations observed in the greyhound have been compared with those of other mammalian species and are discussed here.


Asunto(s)
Perros/orina , Doping en los Deportes/prevención & control , Cromatografía de Gases y Espectrometría de Masas/métodos , Metiltestosterona/orina , Detección de Abuso de Sustancias/métodos , Detección de Abuso de Sustancias/veterinaria , Urinálisis/métodos , Administración Oral , Animales , Metiltestosterona/administración & dosificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Rapid Commun Mass Spectrom ; 22(3): 321-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18181236

RESUMEN

In recent years products containing 6alpha-methylandrost-4-ene-3,17-dione have appeared on the sport supplement market. Scientific studies have proven aromatase inhibition and anabolic and mild androgenic properties; however, no preparation has been approved for medical use up to now. In sports 6alpha-methylandrost-4-ene-3,17-dione has to be classified as a prohibited substance according to the regulations of the World Anti-Doping Agency (WADA). For the detection of its misuse the metabolism was studied following the administration of two preparations obtained from the Internet (Formadrol and Methyl-1-Pro). Several metabolites as well as the parent compounds were synthesized and the structures of 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one, 6alpha-methylandrost-4-ene-3,17-dione, and 5beta-dihydromedroxyprogesterone were confirmed by nuclear magnetic resonance (NMR) spectroscopy. The main metabolite, 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one, was found to be excreted as glucuronide and was still detectable in microg/mL amounts until urine collection was terminated (after 25 h). Additionally, samples from routine human sports doping control had already tested positive for the presence of metabolites of 6alpha-methylandrost-4-ene-3,17-dione. Screening analysis can be easily performed by the existing screening procedure for anabolic steroids using 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one as target substance (limit of detection <10 ng/mL). Its discrimination from the closely eluting drostanolone metabolite, 3alpha-hydroxy-2alpha-methyl-5alpha-androstan-17-one, is possible as the mono-TMS derivative.


Asunto(s)
Doping en los Deportes/prevención & control , Cromatografía de Gases y Espectrometría de Masas/métodos , Metiltestosterona/orina , Detección de Abuso de Sustancias/métodos , Urinálisis/métodos , Adulto , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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