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1.
Artículo en Inglés | MEDLINE | ID: mdl-38581929

RESUMEN

Nandrolone (NT) is a type of androgen anabolic steroid that is often illegally used in cattle farming, leading to unpredictable harm to human health via the food chain. In this study, a rapid detection method for NT in the samples of cattle farming was established using a portable mass spectrometer. The instrument parameters were optimized, including a thermal desorption temperature of 220 °C, a pump speed of 30 %, an APCI ionization voltage of 3900 v, and an injection volume of 6 µL. The samples of bovine urine, feed, sewage, and tissue were selected, and extracted using a solution of methanol:acetonitrile (1:1, v/v), followed by spiking a NT standard solution (1000 ng·mL-1) and ionization through the APCI ion source for detection. The results showed that NT could not be detected in beef and feed due to the complexity of the matrix, while clear signals of NT ions were observed in bovine urine and sewage samples, with LODs of 1000 and 100 ng·mL-1, respectively. Furthermore, quantitative analysis was attempted, and a good linear relationship (R2 = 0.9952) was observed for NT in sewage within the range of 100 to 1000 ng·mL-1. At spiked levels of 100, 500, 1000 and 2000 ng mL-1, the recovery rates ranged from 74.3 % to 92.8 %, with a relative standard deviation (n = 6) of less than 15 %. In conclusion, this detection method offers the advantages of simplicity, rapidity, strong timeliness, and specificity, making it suitable for on-site detection. It can be used for qualitative screening of nandrolone in bovine urine and quantitative analysis of nandrolone in sewage.


Asunto(s)
Límite de Detección , Nandrolona , Bovinos , Animales , Nandrolona/análisis , Nandrolona/orina , Modelos Lineales , Reproducibilidad de los Resultados , Espectrometría de Masas/métodos , Aguas del Alcantarillado/química , Aguas del Alcantarillado/análisis , Alimentación Animal/análisis , Anabolizantes/orina , Anabolizantes/análisis
2.
Biomolecules ; 11(2)2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-33513883

RESUMEN

Nanobody (Nb), a new type of biorecognition element generally from Camelidae, has the characteristics of small molecular weight, high stability, great solubility and high expression level in E. coli. In this study, with 19-nortestosterone (19-NT), an anabolic androgenic steroid as target drug, three specific Nbs against 19-NT were selected from camel immune library by phage display technology. The obtained Nbs showed excellent thermostability and organic solvent tolerance. The nanobody Nb2F7 with the best performance was used to develop a sensitive indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for 19-NT detection. Under optimized conditions, the standard curve of ic-ELISA was fitted with a half-maximal inhibitory concentration (IC50) of 1.03 ng/mL and a detection limit (LOD) of 0.10 ng/mL for 19-NT. Meanwhile, the developed assay had low cross- reactivity with analogs and the recoveries of 19-NT ranged from 82.61% to 99.24% in spiked samples. The correlation coefficient between ic-ELISA and the ultra-performance liquid chromatography/mass spectrometry (UPLC-MS/MS) method was 0.9975, which indicated that the nanobody-based ic-ELISA could be a useful tool for a rapid analysis of 19-NT in animal urine samples.


Asunto(s)
Nandrolona/análisis , Nandrolona/orina , Anticuerpos de Dominio Único/química , Urinálisis/métodos , Orina/química , Animales , Camelidae , Bovinos , Cromatografía Liquida , Ensayo de Inmunoadsorción Enzimática , Industria de Alimentos , Concentración 50 Inhibidora , Límite de Detección , Espectrometría de Masas , Biblioteca de Péptidos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Porcinos
3.
Drug Test Anal ; 9(4): 561-570, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27448217

RESUMEN

Under European legislation, the use of growth promoters is forbidden in food-producing livestock. The application of unofficial protocols with diverse combinations of veterinary drugs, administered in very low concentrations, hinders reliable detection and subsequent operative prevention. It was observed that nandrolone (anabolic steroid) and ractopamine (ß-adrenergic agonist) are occasionally administered to animals, but little is known about their synergic action when they are administered together. Two specific analytical methods based on liquid chromatography-tandem mass spectrometry have been developed, both of which include hydrolysis of the corresponding conjugates. For the nandrolone method, solid-phase extraction was necessary for the complete elimination of the interferences, while employment of the Quantitation Enhanced Data-Dependent scan mode during MS acquisition of ractopamine enabled the utilization of simple liquid-liquid extraction. The nandrolone method was linear in the range of 0.5-25 ng/mL, while the ractopamine calibration curve was constructed from 0.5 to 1000 ng/mL. The corresponding coefficients of correlations were >0.9907. The lower limit of quantification for both methods was 0.5 ng/mL, followed by overall recoveries >81%. Precisions expressed as relative standard deviations were <17%, while matrix effects were minimal. Urine samples taken at the slaughterhouse from veal calves enrolled in an experimental treatment consisting of intramuscular administration of ß-nandrolone-phenylpropionate accompanied with a ractopamine-enriched diet were analysed. Those methods might be useful for studying the elimination patterns of the administered compounds along with characterization of the main metabolic pathways. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Anabolizantes/orina , Bovinos/orina , Sustancias de Crecimiento/orina , Nandrolona/orina , Fenetilaminas/orina , Espectrometría de Masas en Tándem/métodos , Animales , Cromatografía Líquida de Alta Presión/métodos , Inocuidad de los Alimentos , Límite de Detección , Masculino , Detección de Abuso de Sustancias/métodos
4.
Steroids ; 108: 105-11, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26853157

RESUMEN

The use of the anabolic androgenic steroid nandrolone and its prohormones is prohibited in sport. A common route of nandrolone administration is intramuscular injections of a nandrolone ester. Here we have investigated the detection time of nandrolone and 19-norandrosterone and 19-noretiocholanolone metabolites in eleven healthy men after the administration of a 150 mg dose of nandrolone decanoate. The urinary concentrations of nandrolone and the metabolites were monitored by GC-MS/MS for nine months and in some samples the presence of 19-norandrosterone was confirmed by GC/C/IRMS analysis. The participants were genotyped for polymorphisms in PDE7B1 and UGT2B15 genes previously shown to influence the activation and inactivation of nandrolone decanoate. There were large inter-individual variations in the excretion rate of nandrolone and the metabolites, although not related to genetic variations in the UGT2B15 (rs1902023) and PDE7B1 (rs7774640) genes. After the administration, 19-norandrosterone was found at 2-8-fold higher concentrations than 19-noretiocholanolone. We showed that nandrolone doping can be identified 4 and 9 months after the injection of only one single dose in six and three individuals, respectively. We also noted that GC/C/IRMS confirms the presence of exogenous 19-norandrosterone in the urine samples, showing δ13 values around -32 ‰. This was true even in a sample that was not identified as an atypical finding after the GC-MS/MS analysis further showing the power of using GC/C/IRMS in routine anti-doping settings.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Nandrolona/análogos & derivados , Adulto , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Nandrolona/administración & dosificación , Nandrolona/metabolismo , Nandrolona/farmacocinética , Nandrolona/orina , Nandrolona Decanoato
5.
J Forensic Sci ; 59(4): 1025-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24611438

RESUMEN

Anabolic-androgenic steroids (AASs) are frequently misused. To determine causes of death, characteristics, toxicology, and pathology of AAS positive cases, all cases (n = 24) presenting to the New South Wales Department of Forensic Medicine (1995-2012) were retrieved. All were male, and the mean age was 31.7 years. Deaths were mainly due to accidental drug toxicity (62.5%), then suicide (16.7%) and homicide (12.5%). Abnormal testosterone/epitestosterone ratios were reported in 62.5%, followed by metabolites of nandrolone (58.3%), stanozolol (33.3%), and methandienone (20.8%). In 23 of 24 cases, substances other than steroids were detected, most commonly psychostimulants (66.7%). In nearly half, testicular atrophy was noted, as was testicular fibrosis and arrested spermatogenesis. Left ventricular hypertrophy was noted in 30.4%, and moderate to severe narrowing of the coronary arteries in 26.1%. To summarize, the typical case was a male polydrug user aged in their thirties, with death due to drug toxicity. Extensive cardiovascular disease was particularly notable.


Asunto(s)
Anabolizantes/efectos adversos , Andrógenos/efectos adversos , Homicidio , Trastornos Relacionados con Sustancias/epidemiología , Suicidio , Adulto , Anabolizantes/sangre , Anabolizantes/orina , Andrógenos/sangre , Andrógenos/orina , Atrofia , Estenosis Coronaria/patología , Epitestosterona/sangre , Epitestosterona/orina , Humanos , Hipertrofia Ventricular Izquierda/patología , Masculino , Metandrostenolona/sangre , Metandrostenolona/orina , Persona de Mediana Edad , Nandrolona/sangre , Nandrolona/orina , Nueva Gales del Sur/epidemiología , Estanozolol/sangre , Estanozolol/orina , Trastornos Relacionados con Sustancias/sangre , Trastornos Relacionados con Sustancias/orina , Testículo/patología , Testosterona/sangre , Testosterona/orina , Adulto Joven
6.
Biochem Biophys Res Commun ; 446(3): 762-7, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24525129

RESUMEN

Here we report a new method for oxosteroid identification utilizing "tandem mass tag hydrazine" (TMTH) carbonyl-reactive derivatisation reagent. TMTH is a reagent with a chargeable tertiary amino group attached through a linker to a carbonyl-reactive hydrazine group. Thirty oxosteroids were analysed after derivatisation with TMTH by electrospray ionization mass spectrometry (ESI-MS) and were found to give high ion-currents compared to underivatised molecules. ESI-tandem mass spectrometry (MS/MS) analysis of the derivatives yielded characteristic fragmentation patterns with specific mass reporter ions derived from the TMT group. A shotgun ESI-MS method incorporating TMTH derivatisation was applied to a urine sample.


Asunto(s)
Hidrazinas/química , Cetosteroides/orina , Espectrometría de Masa por Ionización de Electrospray/métodos , Corticoesteroides/orina , Andrógenos/orina , Deshidroepiandrosterona/química , Deshidroepiandrosterona/orina , Dihidrotestosterona/química , Dihidrotestosterona/orina , Humanos , Nandrolona/química , Nandrolona/orina , Progestinas/orina , Espectrometría de Masas en Tándem/métodos , Testosterona/química , Testosterona/orina
7.
Drug Test Anal ; 6(4): 376-88, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23949888

RESUMEN

Nandrolone (17ß-hydroxy-4-estren-3-one) is amongst the most misused endogenous steroid hormones in entire male horses. The detection of such a substance is challenging with regard to its endogenous presence. The current international threshold level for nandrolone misuse is based on the urinary concentration ratio of 5α-estrane-3ß,17α-diol (EAD) to 5(10)-estrene-3ß,17α-diol (EED). This ratio, however, can be influenced by a number of factors due to existing intra- and inter-variability standing, respectively, for the variation occurring in endogenous steroids concentration levels in a single subject and the variation in those same concentration levels observed between different subjects. Targeting an efficient detection of nandrolone misuse in entire male horses, an analytical strategy was set up in order to profile a group of endogenous steroids in nandrolone-treated and non-treated equines. Experiment plasma and urine samples were steadily collected over more than three months from a stallion administered with nandrolone laurate (1 mg/kg). Control plasma and urine samples were collected monthly from seven non-treated stallions over a one-year period. A large panel of steroids of interest (n = 23) were extracted from equine urine and plasma samples using a C18 cartridge. Following a methanolysis step, liquid-liquid and solid-phase extractions purifications were performed before derivatization and analysis on gas chromatography-tandem mass spectrometry (GC-MS/MS) for quantification. Statistical processing of the collected data permitted to establish statistical models capable of discriminating control samples from those collected during the three months following administration. Furthermore, these statistical models succeeded in predicting the compliance status of additional samples collected from racing horses.


Asunto(s)
Anabolizantes/sangre , Anabolizantes/orina , Caballos/sangre , Caballos/orina , Nandrolona/sangre , Nandrolona/orina , Anabolizantes/administración & dosificación , Animales , Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas/métodos , Masculino , Nandrolona/administración & dosificación , Espectrometría de Masas en Tándem
8.
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
9.
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
10.
Artículo en Inglés | MEDLINE | ID: mdl-22296620

RESUMEN

The effect of 17ß-19-nortestosterone (17ßNT) treatment of barrows on residue levels and growth was evaluated. Five barrows were treated three times during the fattening period with 17ßNT phenylpropionate (Nandrosol, nandrolone phenylpropionate 50 mg/ml,1 mg/kg body weight). Another five barrows were untreated and five boars (untreated) were kept as positive control. Boars and treated barrows showed a 13 and 9% improvement in growth compared to untreated barrows, with mean final body weights of 121.6, 117.8 and 109.0 kg, respectively. The bulbourethral glands of the treated barrows were three times heavier than untreated barrows. The histology of the prostate and bulbourethral gland of the treated barrows was comparable to the boars, whereas the control barrows showed atrophic glands. Levels of 17ßNT ester in hair from treated barrows were high, whereas boars and untreated barrows did not show levels above LLQ. It is concluded that analysis of hair can detect illegal treatment with 17ßNT ester in barrows. The size of the bulbourethral gland can also be used for screening in the slaughterhouse.


Asunto(s)
Anabolizantes/farmacología , Genitales Masculinos/efectos de los fármacos , Cabello/química , Nandrolona/análogos & derivados , Sus scrofa/crecimiento & desarrollo , Aumento de Peso/efectos de los fármacos , Anabolizantes/análisis , Anabolizantes/farmacocinética , Anabolizantes/orina , Animales , Glándulas Bulbouretrales/citología , Glándulas Bulbouretrales/efectos de los fármacos , Glándulas Bulbouretrales/crecimiento & desarrollo , Crimen , Cruzamientos Genéticos , Contaminación de Alimentos/prevención & control , Genitales Masculinos/citología , Genitales Masculinos/crecimiento & desarrollo , Masculino , Industria para Empaquetado de Carne/métodos , Nandrolona/análisis , Nandrolona/farmacocinética , Nandrolona/farmacología , Nandrolona/orina , Países Bajos , Orquiectomía/veterinaria , Tamaño de los Órganos/efectos de los fármacos , Próstata/citología , Próstata/efectos de los fármacos , Sus scrofa/metabolismo , Testículo/citología , Testículo/efectos de los fármacos , Testículo/crecimiento & desarrollo , Distribución Tisular
11.
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
12.
Yao Xue Xue Bao ; 47(12): 1667-70, 2012 Dec.
Artículo en Chino | MEDLINE | ID: mdl-23460974

RESUMEN

A method was evaluated for determination of twenty-one doping (including nandrolone, boldenone and methandienone) in human urine by gas chromatography-high resolution mass spectrometry. Samples were prepared by liquid-liquid extraction, concentrated, TMS derivatization and limit of detection at ng x mL(-1) by MID/GC/HRMS. According to the code of the World Anti-Doping Agency (WADA), precision and recoveries of the procedure were evaluated by replicate analysis (n = 6), the recoveries in the range of 66%-103%, with the RSD below 10.0%. The precision within the day of the method with three different concentrations was also determined RSD were less than 9.5%, 10.0% and 9.7%.


Asunto(s)
Anabolizantes/orina , Doping en los Deportes , Metandrostenolona/orina , Nandrolona/orina , Testosterona/análogos & derivados , Cromatografía de Gases y Espectrometría de Masas , Humanos , Detección de Abuso de Sustancias/métodos , Testosterona/orina
13.
J Steroid Biochem Mol Biol ; 128(1-2): 1-11, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22051080

RESUMEN

19-Norandrostenedione (NAED) and nandrolone are anabolic-androgenic steroids (AASs). Nandrolone was regarded solely as a synthetic AAS until the 1980s when trace concentrations of apparently endogenous nandrolone were detected in urine samples obtained from intact male horses (stallions). Since then, its endogenous origin has been reported in boars and bulls; endogenous NAED and nandrolone have been identified in plasma and urine samples collected from stallions. More recently, however, it was suggested that NAED and nandrolone detected in urine samples from stallions are primarily artifacts due to the analytical procedure. The present study was undertaken to determine whether NAED and nandrolone detected in plasma and urine samples collected from stallions are truly endogenous or artifacts from sample processing. To answer this question, fresh plasma and urine samples from ≥8 stallions were analyzed for the two AASs, soon after collection, by liquid chromatography hyphenated to tandem mass spectrometry (LC-MS/MS). NAED and nandrolone were not detected in fresh plasma samples but detected in the same samples post storage. Concentrations of both AASs increased with storage time, and the increases were greater at a higher storage temperature (37°C versus 4°C, and ambient temperature versus 4°C). Although NAED was detected in some fresh stallion urine samples, its concentration (<407 pg/mL) was far lower (<0.4%) than that in the same samples post storage (at ambient temperature for 15 days). Nandrolone was not detected in most of fresh urine samples but detected in the same samples post storage. Based on these results, it is concluded that all NAED and nandrolone detected in stored plasma samples of stallions and most of them in the stored urine samples are not from endogenous origins but spontaneously generated during sample storage, most likely from spontaneous decarboxylation of androstenedione-19-oic acid and testosterone-19-oic acid. To our knowledge, it is the first time that all NAED and nandrolone detected in plasma of stallions and most of them detected in the urine have been shown to be spontaneously generated in vitro during sample storage. This finding would have significant implications with regard to the regulation of the two steroids in horse racing.


Asunto(s)
Anabolizantes/orina , Androstenodiona/análogos & derivados , Artefactos , Caballos/orina , Nandrolona/orina , Anabolizantes/sangre , Androstenodiona/sangre , Androstenodiona/orina , Animales , Calibración , Cromatografía Liquida , Doping en los Deportes , Femenino , Caballos/sangre , Masculino , Nandrolona/sangre , Manejo de Especímenes/métodos , Espectrometría de Masas en Tándem , Factores de Tiempo
14.
Anal Chim Acta ; 700(1-2): 2-10, 2011 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-21742110

RESUMEN

Despite the growing importance of qualitative screening tests in routine laboratories involved in the EU official control, their validation is not as deeply explained in Commission Decision 2002/657/EC as the validation of quantitative confirmatory methods. At the same time, the issue of quality assurance of screening assays defining internal quality control (IQC) procedures as required by accreditation bodies is undoubtedly less developed in this analytical field. As an example the present study describes the development, the validation and the IQC implemented for a commercial enzyme linked immunosorbent assay (ELISA) able to detect 17-α-19-nortestosterone (α-NT) and 17-ß-19-nortestosterone (ß-NT) isomers in bullock urine. In order to select a suitable sample treatment, two SPE purification protocols were preliminary compared. The chosen method was therefore fully validated determining the mandatory parameters required by Commission Decision 2002/657/EC: specificity, detection capability and robustness. An in-depth discussion was carried out illustrating the possible validation approaches and their implications especially in the assessment of the key performance characteristic: detection capability. Finally, the control charts implemented for continuous method verification during analyses of real samples were reported.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Nandrolona/orina , Animales , Bovinos , Ensayo de Inmunoadsorción Enzimática/normas , Isomerismo , Masculino , Nandrolona/aislamiento & purificación , Nandrolona/normas , Control de Calidad , Extracción en Fase Sólida/métodos
15.
Bioanalysis ; 2(12): 1971-88, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21110741

RESUMEN

BACKGROUND: Within equine drug surveillance, there is significant interest in analyzing intact phase II conjugates of drugs in urine, but progress has been limited by a lack of reference material. METHOD: In this study, in vitro techniques using equine liver fractions were employed to produce glucuronide and sulfate conjugates of stanozolol, 16ß-hydroxystanozolol and nandrolone, the glucuronide conjugate of morphine and the glutathione metabolite of chlordinitrobenzene for the first time in equine sports drug surveillance. RESULTS: The glucuronide conjugate of the synthetic progestagen altrenogest was also produced in vitro, removing the requirement for sample hydrolysis during routine urinalyses. CONCLUSION: These results highlight the potential of in vitro studies for the production of phase II reference material, allowing the development of assays based on intact conjugates.


Asunto(s)
Anabolizantes/metabolismo , Doping en los Deportes , Glucurónidos/metabolismo , Glutatión/metabolismo , Hígado/metabolismo , Esteroides/metabolismo , Detección de Abuso de Sustancias/métodos , Anabolizantes/orina , Animales , Dinitroclorobenceno/metabolismo , Dinitroclorobenceno/orina , Glucurónidos/orina , Glutatión/orina , Caballos , Morfina/análisis , Morfina/metabolismo , Nandrolona/metabolismo , Nandrolona/orina , Progestinas/metabolismo , Progestinas/orina , Estanozolol/análogos & derivados , Estanozolol/metabolismo , Estanozolol/orina , Esteroides/orina
16.
Rapid Commun Mass Spectrom ; 24(13): 1881-94, 2010 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-20533318

RESUMEN

Nandrolone (19-nortestosterone) is an androgenic anabolic steroid illegally used as a growth-promoting agent in animal breeding and as a performance enhancer in athletics. Therefore, its use was officially banned in 1974 by the Medical Commission of the International Olympic Committee (IOC). Following nandrolone administration, the main metabolites in humans are 19-norandrosterone, 19-norethiocolanolone and 19-norepiandrosterone, and their presence in urine is the basis of detecting its abuse. The present work was undertaken to determine, in human urine, nandrolone metabolites (phase I and phase II) by developing and comparing multiresidue liquid chromatography/tandem mass spectrometry (LC/MS/MS) and gas chromatography/mass spectrometry (GC/MS) methods. A double extraction by solid-phase extraction (SPE) was necessary for the complete elimination of the interfering compounds. The proposed methods were also tested on a real positive sample, and they allow us to determine the conjugated/free fractions ratio reducing the risk of false positive or misleading results and they should allow laboratories involved in doping control analysis to monitor the illegal use of steroids. The advantages of LC/MS/MS over GC/MS (which is the technique mainly used) include the elimination of the hydrolysis and derivatization steps: it is known that during enzymatic hydrolysis several steroids can be converted into related compounds and deconjugation is not always 100% effective. The validation parameters for the two methods were similar (limit of quantification (LOQ) <1 ng/mL and percentage coefficient of variance (CV%) <16.4), and both were able to confirm unambiguously all the analytes, thus confirming the validity of both techniques.


Asunto(s)
Cromatografía Liquida/métodos , Estranos/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Nandrolona/orina , Espectrometría de Masas en Tándem/métodos , Doping en los Deportes , Estranos/química , Estranos/metabolismo , Femenino , Humanos , Masculino , Nandrolona/química , Nandrolona/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Extracción en Fase Sólida/métodos
17.
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
18.
Med Sci Sports Exerc ; 42(4): 754-61, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19952830

RESUMEN

INTRODUCTION: This study examined the influence of a supplement matrix on the excretion pattern of nandrolone metabolites in response to ingestion of a trace amount of 19-norandrostenedione. METHODS: Ten male and nine female volunteers (mean ± SD: age = 26 ± 3 yr, height = 1.71 ± 0.09 m, body mass = 70.9 ± 13.2 kg) were recruited. On two occasions, subjects entered the laboratory in the morning after an overnight fast. After an initial urine collection, subjects ingested either 500 mL of plain water or a commercially available energy bar; 10 µg of 19-norandrostenedione was added to each. The volume of each urine sample passed during the next 24 h was measured, and an aliquot was retained for analysis. All samples were analyzed for the metabolites 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) by gas chromatography-mass spectrometry. RESULTS: The total volume of urine passed was higher in the water trial (2.10 ± 0.52 L) than in the bar trial (1.85 ± 0.55 L; P = 0.040). Baseline urinary 19-NA concentrations were all below the limit of quantification for the assay. Peak urinary 19-NA was lower (P = 0.002) in the water trial (4.80 ± 2.84 ng·mL(-1)) than in the bar trial (8.46 ± 4.44 ng·mL(-1)). The time elapsed between ingestion of the supplement and the peak urinary 19-NA concentration was longer (P = 0.023) on the bar trial (4.6 ± 2.4 h) than on the water trial (2.8 ± 1.9 h). There was no difference in the total recovery of 19-NA + 19-NE between the liquid and solid supplements (water 30 ± 10%; bar 28 ± 12%; P < 0.140). CONCLUSIONS: Peak 19-NA concentrations were higher, and occurred later, when the 19-norandrostenedione was added to a solid supplement. This may be due to a slower rate of absorption and/or a reduced diuresis, resulting in a longer period for the metabolites to accumulate in the urine.


Asunto(s)
Anabolizantes/administración & dosificación , Androstenodiona/análogos & derivados , Suplementos Dietéticos , Nandrolona/orina , Adsorción , Adulto , Anabolizantes/farmacocinética , Androstenodiona/administración & dosificación , Androstenodiona/farmacocinética , Doping en los Deportes , Ingestión de Líquidos , Ingestión de Alimentos , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Adulto Joven
19.
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
20.
Scand J Med Sci Sports ; 20(1): 90-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19170961

RESUMEN

We investigated the effects of the menstrual cycle, oral contraception and physical training on exhaustive exercise-induced changes in the excretion of nandrolone metabolites [19-norandrosterone (19-NA), and 19-noretiocholanolone (19-NE)] in young women. Twenty-eight women were allocated to an untrained group (n=16) or a trained group (n=12), depending on their physical training background. The untrained group was composed of nine oral contraceptive users (OC+) and seven eumenorrheic women (OC-), while the trained group was entirely composed of OC+ subjects. Three laboratory sessions were conducted in a randomized order: a prolonged exercise test, a short-term exercise test and a control session. Urine specimens were collected before and 30, 60 and 90 min after the exercise test and at the same times of the day during the control session. Urinary concentrations of nandrolone metabolites were determined by gas chromatography coupled to mass spectrometry. Urinary concentrations of 19-NA and 19-NE ranged from undetectable levels to 1.14 and 0.47 ng/mL, respectively. Nandrolone excretion was not affected by the menstrual cycle phase (early follicular vs mid-luteal), prior physical training, oral contraception or acute physical exercise. Therefore, a urinary concentration of 2 ng/mL of 19-NA appears to be fair as the upper acceptable limit in doping control tests for female athletes.


Asunto(s)
Ejercicio Físico/fisiología , Nandrolona/orina , Adolescente , Adulto , Androsterona/orina , Anticonceptivos Orales/farmacología , Creatinina/metabolismo , Doping en los Deportes , Etiocolanolona/orina , Prueba de Esfuerzo , Femenino , Fase Folicular/orina , Humanos , Fase Luteínica/orina , Consumo de Oxígeno , Adulto Joven
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