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1.
Drug Test Anal ; 14(11-12): 1864-1870, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36258640

RESUMEN

The detection of a putative 18-methyl-19-nortestosterone metabolite in a forensic bodybuilder's urine sample collected as part of a criminal proceeding has triggered a follow-up investigation. Four different dietary supplements in the possession of the suspect were examined with regard to possible precursor steroids. This led to the detection of the declared ingredient methoxydienone, which was confirmed by both, GC-MSMS and LC-HRMSMS. As neither 18-methyl-testosterone, nor 18-methyl-19-nortestosterone were detectable in the supplements, the possibility that the metabolite originates from methoxydienone was investigated. For this purpose, the metabolic fate of methoxydienone was studied in vitro using human HepG2 cells and in vivo by a single oral administration. While the 18-methyl-19-nortestosterone metabolite was not generated by HepG2 cells incubated with methoxydienone, it was observed in the urine samples collected at 2, 6, 10 and 24 h after methoxydienone administration. Moreover, the potential binding of methoxydienone as ligand to the human androgen receptor was modelled in silico in comparison with 18-methylnandrolone, for which androgen receptor activation had been shown in an in vitro approach before. In conclusion, we could ascribe the presence of the 18-methyl-19-nortestosterone metabolite in a forensic urine sample to originate from methoxydienone present in dietary supplements. Methoxydienone was observed to slowly degrade by demethylation of the methoxy substituent in liquid solutions. While no compound-specific intermediates were identified that allowed differentiation from other 18-methyl steroids, the 18-methyl-19-nortestosterone metabolite proved to be a suitable marker for reliable detection in doping analysis.


Asunto(s)
Doping en los Deportes , Nandrolona , Humanos , Receptores Androgénicos , Esteroides/análisis , Andrógenos , Suplementos Dietéticos , Nandrolona/análisis
2.
J Chromatogr Sci ; 58(4): 355-361, 2020 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-32099999

RESUMEN

A high-performance liquid chromatography method employing a diode-array detector and mass spectrometry detector was developed, validated and implemented for determining Synephrine, Caffeine, Clenbuterol, Nandrolone, Testosterone and Methylhexaneamine in Nutritional supplements. The use of Nutritional supplements is widespread. Hazards relating to concentration, composition, individual contaminants, supplements interactions as well as positive doping results among athletes present increasing concerns regarding nutritional supplement consuming. The proposed method was validated according to the International Conference on the Harmonization of the Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) standards. The proposed method observed to be accurate, linear, precise, sensitive, required minimal sample preparation and uncomplicated mobile phase. The implementation of the proposed method on nine commercial supplements shows that inaccurate labeling for some supplements regarding the concentration of the ingredients.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Espectrometría de Masas/métodos , Congéneres de la Testosterona/análisis , Aminas/análisis , Cafeína/análisis , Estimulantes del Sistema Nervioso Central/análisis , Cromatografía Liquida/métodos , Clenbuterol/análisis , Nandrolona/análisis , Reproducibilidad de los Resultados , Sinefrina/análisis
3.
Drug Test Anal ; 9(4): 553-560, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27367148

RESUMEN

Avidin-biotin technology was used for the implementation of an enzyme-linked immunosorbent assay (AB-ELISA) as a sensitive method for the detection of anabolic androgenic steroids (AAS) present in dietary supplements. Using click chemistry, novel haptens (linker-optimized biotinylated nandrolone (NT) and testosterone (T) at positions C-3 and C-17, respectively) were designed and synthesized to be then applied as four different immobilized competitors in a proposed set of four indirect competitive AB-ELISAs. Four rabbit polyclonal antibodies of various specificities were prepared using four different immunogens synthesized from C-3 and C-17 carboxymethyloxime and hemisuccinate derivatives of NT and T, respectively. Assembled AB-ELISAs were characterized to establish method parameters such as a half-maximum inhibition concentration (0.18-12.99 ng/mL), limit of detection (0.004-0.032 ng/mL) and linear working range (the best with 0.02-1.38 ng/mL). The stability of the set simulating storage in different conditions was demonstrated. Cross reactivity (CR) was tested for 59 steroids including both endogenous and synthetic analogues in four assembled AB-systems. The focus was placed on the practical use of the method in detection of various AAS in 49 samples of counterfeit dietary supplements. The concordance between ultra high performance liquid chromatography-mass spectrometry (UHPLC-MS) and the CR corrected data from AB-ELISA indicated the potential of this method even to quantification of T propionate, NT phenyl propionate, and NT decanoate in such a complex matter. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Anabolizantes/análisis , Suplementos Dietéticos/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Nandrolona/análisis , Testosterona/análisis , Animales , Avidina/química , Biotina/química , Límite de Detección , Conejos
4.
Handb Exp Pharmacol ; (195): 127-54, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20020363

RESUMEN

Nandrolone or nortestosterone, an anabolic-androgenic steroid, has been prohibited by doping control regulations for more than 30 years. Although its main metabolism in the human body was already known at that time, and detection of its misuse by gas or liquid chromatographic separation with mass spectrometric detection is straightforward, many interesting aspects regarding this doping agent have appeared since.Over the years, nandrolone preparations have kept their position among the prohibited substances that are most frequently detected in WADA-accredited laboratories. Their forms of application range from injectable fatty acid esters to orally administered nandrolone prohormones. The long detection window for nandrolone ester preparations and the appearance of orally available nandrolone precursors have changed the pattern of misuse.At the same time, more refined analytical methods with lowered detection limits led to new insights into the pharmacology of nandrolone and revelation of its natural production in the body.Possible contamination of nutritional supplements with nandrolone precursors, interference of nandrolone metabolism by other drugs and rarely occurring critical changes during storage of urine samples have to be taken into consideration when interpreting an analytical finding.A set of strict identification criteria, including a threshold limit, is applied to judge correctly an analytical finding of nandrolone metabolites. The possible influence of interfering drugs, urine storage or natural production is taken into account by applying appropriate rules and regulations.


Asunto(s)
Anabolizantes/farmacología , Doping en los Deportes , Nandrolona/farmacología , Inhibidores de 5-alfa-Reductasa , Anabolizantes/efectos adversos , Anabolizantes/análisis , Anabolizantes/metabolismo , Anabolizantes/orina , Suplementos Dietéticos , Contaminación de Medicamentos , Inhibidores Enzimáticos/farmacología , Femenino , Contaminación de Alimentos , Humanos , Masculino , Ciclo Menstrual/fisiología , Nandrolona/efectos adversos , Nandrolona/análisis , Nandrolona/metabolismo , Nandrolona/orina , Embarazo , Progestinas/farmacología
5.
J Chromatogr Sci ; 43(1): 2-6, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15808000

RESUMEN

A sensitive and selective method for the screening of anabolizing agents in aqueous nutritional supplements is described and validated. A total of 28 different anabolizing agents are screened for, including testosterone and prohormones, nandrolone and prohormones, stanozolol, and metandienone. The different analytes are extracted from the aqueous nutritional supplements by liquid-liquid extraction with a mixture of pentane and freshly distilled diethylether (1:1) after the supplements have been made alkaline with a NaHCO3-K2CO3 (2:1) buffer. The anabolizing agents are derivatized with a mixture of MSTFA-NH4I-ethanethiol (320:1:2) as routinely used for the screening of anabolic steroids extracted from urine. The derivatives are analyzed by gas chromatography (GC)-mass spectrometry (MS) in the selective ion monitoring mode. The limits of detection range from 1 to 10 ng/mL. One aqueous nutritional supplement (creatine serum) was analyzed with this screening method and was found to contain dehydroepiandrosterone (DHEA) at very low concentrations. The presence of DHEA could be confirmed with GC-MS-MS. Results of the application of this method and a similar method for solid nutritional supplements previously described are given.


Asunto(s)
Anabolizantes/análisis , Suplementos Dietéticos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Deshidroepiandrosterona/análisis , Doping en los Deportes/prevención & control , Indicadores y Reactivos , Metandrostenolona/análisis , Nandrolona/análisis , Fenómenos Fisiológicos de la Nutrición , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estanozolol/análisis , Testosterona/análisis , Agua
6.
Food Addit Contam ; 21(7): 632-40, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15370836

RESUMEN

Recent studies showed that non-hormonal supplements such as vitamins, minerals and amino acids can contain anabolic androgenic steroids not declared on the labels of the products. These undeclared substances (often prohormones of testosterone or 19-nortestosterone) can cause health risks to consumers and might lead to positive results in sports doping control, especially for the nandrolone metabolite norandrosterone. The analysis of nutritional supplements for anabolic steroids has proven to be rather difficult due to the different matrices in the various products. To conduct a broad-based analysis, a few robust methods capable of analysing various matrices are needed. To obtain a sensitive gas chromatography-mass spectrometry (GC-MS) analysis, a method including extraction and purification of the analytes followed by GC-MS analysis of the trimethylsilyl (TMS) derivatives of the steroids was developed. The limit of detection was improved by the addition of a mixture of 1-N,N-diisopropylamino-n-alkanes (DIPAs) to the final extract. In pure creatine monohydrate powder the limits of detection were demonstrated to be 0.1 ng microg (-1) for dehydroepiandrosterone (DHEA) and estr-4-ene-3beta,17beta-diol, 0.7 ng g(-1) for 5alpha-androstane-3beta,17beta-diol and androsta-1,4-diene-3,17-dione, 1 ng g(-1) for estr-5-ene-3beta,17beta-diol, estr-4-ene-3,17-dione, 19-nortestosterone, androst-4-ene-3, 17-dione and testosterone, and 2 ng g(-1) for androst-4-ene-3beta,17beta-diol and androst-5-ene-3beta,17beta-diol. The recovery (determined at 200 ng g(-1)) ranged from 32% for 19-nortestosterone to 92% for androst-5-ene-3beta,17beta-diol. During the investigation of different nutritional supplements, several analytical difficulties occurred. Aspects of homogenization, extraction, separation, derivatization and GC-MS measurement as well as strategies for the solution of problems arising were optimized. For quantitative measurements of the steroids in nutritional supplements, deuterated internal standards of the specific steroids or standard addition are necessary to compensate for matrix effects.


Asunto(s)
Anabolizantes/análisis , Suplementos Dietéticos/análisis , Alcanos , Androstadienos/análisis , Androstano-3,17-diol/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Nandrolona/análisis , Testosterona/análisis , Compuestos de Trimetilsililo/análisis
7.
J Pharm Biomed Anal ; 25(5-6): 843-52, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11377067

RESUMEN

A method is described for the determination of anabolic steroids including testosterone, 19-nor-4-androstene-3,17-dione, 4-androstene-3,17-dione and nandrolone in food supplements. Initial clean-up is done by HPLC followed by determination with GC/MS. A 'contaminated' food supplement was analysed and appeared to contain 19-nor-4-androstene-3,17-dione and 4-androstene-3,17-dione. One capsule of this nutritional supplement was ingested by five male volunteers. Urine samples were collected and analysed by GC/MS and GC/MS-MS. Neither the ratio testosterone/epitestosterone, nor the ratio androstenedione/epitestosterone increased significantly. Concentrations above 2 ng/ml for norandrosterone, the major metabolite of nandrolone, were detected until 48-144 h after ingestion of the food supplement.


Asunto(s)
Anabolizantes/análisis , Suplementos Dietéticos/análisis , Anabolizantes/orina , Androstenodiona/análogos & derivados , Androstenodiona/análisis , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Nandrolona/análisis , Testosterona/análisis
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