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1.
Food Chem ; 458: 139842, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38996490

RESUMO

One of the principal byproducts of coffee roasting is the coffee parchment. It is abundant in bioactive substances, including derivatives of chlorogenic acids, which are well-known for their exceptional antioxidant effects. It is advantageous to use environmentally friendly extraction techniques on such residues since it adds value to the entire coffee production process supply chain. The aim of this work was to assess and enhance the ability of non-conventional extraction techniques to extract derivatives of chlorogenic acid from coffee parchment. A central composite design was used to maximize the recovery of those phenolic compounds. The optimized extraction conditions were with 5 min extraction period, at a temperature of 70 °C, and 80% ethanol in the extractor solvent. In this conditions extraction recovery of chlorogenic acids was of 0.8% by the use of microwave-aided extraction (MAE). The optimized conditions are practical, economical, and ecologically friendly method to extract phenolic compounds and, consequently, underscores the potential for sustainable utilization of coffee parchment, offering a valuable contribution to the development of environmentally conscious strategies within the coffee industry.


Assuntos
Ácido Clorogênico , Coffea , Café , Extratos Vegetais , Ácido Clorogênico/isolamento & purificação , Ácido Clorogênico/química , Ácido Clorogênico/análise , Coffea/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Café/química , Fracionamento Químico/métodos , Fracionamento Químico/instrumentação , Micro-Ondas , Temperatura Alta
2.
J Pharm Sci ; 113(8): 2542-2551, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38815860

RESUMO

Rotigotine (RTG) is a dopamine agonist used in the treatment of Parkinson's disease. As it is susceptible to oxidation, stability studies must be carefully designed for the identification and characterization of all possible degradation products. Here, RTG degradation was evaluated according to the International Conference on Harmonization guidelines under various stress conditions, including acidic and basic hydrolysis, oxidative, metallic, photolytic, and thermal conditions. Additionally, more severe stress conditions were applied to induce RTG degradation. Significant degradation was only observed under oxidative and photolytic conditions. The samples were analyzed by high performance liquid chromatography coupled to photodiode array detectors, charged aerosol, and high-resolution mass spectrometry. Chromatographic analyses revealed the presence of eight substances related to RTG, four of which were already described and were qualified impurities (impurities B, C, K and E) and four new degradation products (DP-1 - DP-4), whose structures were characterized by high-resolution mass spectrometry through Q-Orbitrap and electrospray ionization. In the stress testing of the active pharmaceutical ingredient in solid form, significant RTG degradation was observed in the presence of the oxidative matrix. The results corroborate the literature that confirm the high susceptibility of RTG to oxidation and the importance of using different detectors to detect degradation products in forced degradation studies.


Assuntos
Estabilidade de Medicamentos , Espectrometria de Massas por Ionização por Electrospray , Tetra-Hidronaftalenos , Tiofenos , Cromatografia Líquida de Alta Pressão/métodos , Tiofenos/química , Tiofenos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Tetra-Hidronaftalenos/química , Tetra-Hidronaftalenos/análise , Oxirredução , Agonistas de Dopamina/análise , Agonistas de Dopamina/química , Hidrólise , Contaminação de Medicamentos/prevenção & controle , Fotólise
3.
Nat Prod Res ; : 1-5, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767203

RESUMO

Aqueous and hydroalcoholic extracts from the pulp of Ambelania acida Aubl. (Apocynaceae) fruits were subjected to analysis through UHPLC-HRMS and antioxidant potential using the TPC, DPPH, ABTS, FRAP, and ORAC assays. A putative identification of the compounds carried out by comparison of the fragmentation spectra revealed the predominance of the monoterpene indole alkaloids tabersonine, pseudocopsinine, ajmalicine, and strictosidine. Additionally, gallic acid, caffeic acid, citric acid, 3-O-p-coumaroylquinic acid, chlorogenic acid, catechin, ellagic acid, eschweilenol C (ellagic acid deoxyhexoside), and sucrose were identified. In face of the phenolic compounds observed, hydroalcoholic extract showed a higher antioxidant activity compared to the aqueous extract, observed at TPC (108.85 mg GAE/100g), FRAP (0.73 µmol Fe2SO4/g), DPPH (1221.76 µmol TE/g), ABTS (3460.00 µmol TE/g), and ORAC assays (120.47 µmol TE/g). These findings underscore the abundant presence of bioactive compounds, including phenolics and alkaloids, in an edible Amazonian fruit.

4.
Plants (Basel) ; 13(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38592892

RESUMO

Ocotea, the largest genus in the Lauraceae family, encompasses numerous species of scientific interest. However, most Ocotea species have only been described morphologically. This study used an untargeted metabolomics workflow with UHPLC-HRMS and GNPS-FBMN to provide the first chemical evaluation of the polar specialized metabolites of O. delicata leaves. Leaves from three O. delicata specimens were extracted using ultrasound-assisted extraction with 70% ethanol. Among the examined samples, 44 metabolites, including alkaloids and flavonoids, were identified. In contrast to other Ocotea species, O. delicata has a wider diversity of kaempferol derivatives than quercetin. The biomass of the specimens showed a significant correlation with the chemical profile. The similarity among specimens was mostly determined by the concentrations of quinic acid, kaempferol glycosides, and boldine. The evaluated specimens exhibited chemical features similar to those of species classified as New World Ocotea, with the coexistence of aporphine and benzylisoquinoline alkaloids.

5.
J Chromatogr A ; 1708: 464362, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37717453

RESUMO

Psychedelic compounds have gained renewed interest for their potential therapeutic applications, but their metabolism and effects on complex biological systems remain poorly understood. Here, we present a systematic characterization of Lysergic Acid Diethylamide (LSD) metabolites in the model organism Caenorhabditis elegans using state-of-the-art analytical techniques. By employing ultra-high performance liquid chromatography coupled with high-resolution tandem mass spectrometry, we putatively identified a range of LSD metabolites, shedding light on their metabolic pathways and offering insights into their pharmacokinetics. Our study demonstrates the suitability of Caenorhabditis elegans as a valuable model system for investigating the metabolism of psychedelic compounds and provides a foundation for further research on the therapeutic potential of LSD.


Assuntos
Caenorhabditis elegans , Alucinógenos , Animais , Cromatografia Líquida de Alta Pressão , Dietilamida do Ácido Lisérgico , Espectrometria de Massas em Tandem
6.
Metabolites ; 13(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36837895

RESUMO

In this study, a beetroot peel flour was made, and its in vitro antioxidant activity was determined in aqueous (BPFw) and ethanolic (BPFe) extracts. The influence of BPFw on breast cancer cell viability was also determined. A targeted betalain profile was obtained using high-resolution Q-Extractive Plus Orbitrap mass spectrometry (Obrtitrap-HRMS) alongside untargeted chemical profiling of BPFw using Ultra-High-Performance Liquid Chromatography with High-Resolution Mass Spectrometry (UHPLC-HRMS). BPFw and BPFe presented satisfactory antioxidant activities, with emphasis on the total phenolic compounds and ORAC results for BPFw (301.64 ± 0.20 mg GAE/100 g and 3032.78 ± 55.00 µmol T/100 g, respectively). The MCF-7 and MDA-MB-231 breast cancer cells presented reductions in viability when treated with BPFw, showing dose-dependent behavior, with MDA-MB-231 also showing time-dependent behavior. The chemical profiling of BPFw led to the identification of 9 betalains and 59 other compounds distributed amongst 28 chemical classes, with flavonoids and their derivates and coumarins being the most abundant. Three forms of betalain generated via thermal degradation were identified. However, regardless of thermal processing, the BPF still presented satisfactory antioxidant and anticancer activities, possibly due to synergism with other identified molecules with reported anticancer activities via different metabolic pathways.

7.
Drug Test Anal ; 15(3): 292-298, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36346023

RESUMO

Blood transfusion is performed by cheating athletes to rapidly increase oxygen delivery to exercise muscles and enhance their performance. This method is banned by the World Anti-doping Agency (WADA). Heterologous or allogenic blood transfusion happens when blood from a different person is transfused. The method used to detect this type of doping is based on flow cytometry, by identifying variations in blood group minor antigens present on the red blood cells' surface. Transfusion practices have regained interest since the introduction of human recombinant erythropoietin detection method. It has been reported that the number of occurrences of two athletes sharing an identical phenotype in the same sport was five times higher than the theoretical populational probability. The present work describes the prevalence of 10 erythrocytes surface antigens in a population of 261 athletes from all five continents. The matching phenotype per sport is also described.


Assuntos
Dopagem Esportivo , Esportes , Humanos , Transfusão de Sangue , Eritrócitos , Atletas
9.
Nat Prod Res ; 36(4): 984-988, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33103472

RESUMO

The metabolic fingerprint of a non-volatile fraction of Ocotea canaliculata (Rich.) Mez (Lauraceae) leaves was determined by UHPLC-HRMS analysis. Twenty-four compounds were suggestively identified by GNPS-FBMN. The results revealed a large production of flavonoids, mainly flavones and flavanones, a chemical class poorly described in the Ocotea genus. Within the identified compounds, four are being described for the first time in this genus. The major metabolite detected was astilbin, with a concentration corresponding to 23.2 ± 1.58% of the extracts. The expressive content of astilbin also highlights it as a chemical marker for the species. As a species that is classified as a complex, qualitative and semi-quantitative features obtained through the O. canaliculata flavonoid fingerprint can be further used for a more precise circumscription and species-specific characterization.


Assuntos
Lauraceae , Ocotea , Cromatografia Líquida de Alta Pressão , Lauraceae/química , Ocotea/química , Extratos Vegetais/química , Folhas de Planta/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-34801941

RESUMO

Coffee is one of the most consumed beverages worldwide. Cafestol is an endogenous coffee diterpene present in raw coffee beans and also found in hot beverages, with several biological activities. However, there is still little information on this molecule after ingestion of coffee infusion. Zebrafish (Danio rerio) is a promising in vivo model for metabolic studies due to the annotation of mammalian orthologs to encode enzymes related to drug metabolism. Experiments using Zebrafish Water Tank (ZWT) model produce more significant number of metabolites for molecular investigation in a cleaner matrix than other classical models, such as purified hepatocytes. This work aimed to investigate the biotransformation of cafestol by the ZWT model using ultra-performance liquid chromatography coupled to hybrid quadrupole-orbitrap high-resolution mass spectrometry equipped with electrospray ionization (UPLC-HRMS) supported by in silico approach using SMARTCyp, Way2Drug and XenoSite Softwares. Twenty-five metabolites of cafestol were proposed by in silico analysis, in which 5 phase I metabolites were confirmed in the ZWT by UPLC and MS/HRMS investigation: 6-hydroxy-cafestol, 6,12-dihydroxy-cafestol, 2-oxo-cafestol, 6-oxo-cafestol and one isomer whose position in the carboxyl group was not determined. These metabolites were observed during 9 h of the experiment, whose contents were associated with the behavioral responses of the fish.


Assuntos
Diterpenos/química , Diterpenos/metabolismo , Peixe-Zebra/metabolismo , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Café/química , Café/metabolismo , Simulação por Computador , Espectrometria de Massas , Modelos Animais , Estrutura Molecular
11.
Biomed Pharmacother ; 141: 111857, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34323702

RESUMO

Quinoline and 1,2,3-triazoles are well-known nitrogen-based heterocycles presenting diverse pharmacological properties, although their antileishmanial activity is still poorly exploited. As an effort to contribute with studies involving these interesting chemical groups, in the present study, a series of compounds derived from 4-aminoquinoline and 1,2,3-triazole were synthetized and biological studies using L. amazonensis species were performed. The results pointed that the derivative 4, a hybrid of 4-aminoquinoline/1,2,3-triazole exhibited the best antileishmanial action, with inhibitory concentration (IC50) values of ~1 µM against intramacrophage amastigotes of L. amazonensis , and being 16-fold more active to parasites than to the host cell. The mechanism of action of derivative 4 suggest a multi-target action on Leishmania parasites, since the treatment of L. amazonensis promastigotes caused mitochondrial membrane depolarization, accumulation of ROS products, plasma membrane permeabilization, increase in neutral lipids, exposure of phosphatidylserine to the cell surface, changes in the cell cycle and DNA fragmentation. The results suggest that the antileishmanial effect of this compound is primarily altering critical biochemical processes for the correct functioning of organelles and macromolecules of parasites, with consequent cell death by processes related to apoptosis-like and necrosis. No up-regulation of reactive oxygen and nitrogen intermediates was promoted by derivative 4 on L. amazonensis -infected macrophages, suggesting a mechanism of action independent from the activation of the host cell. In conclusion, data suggest that derivative 4 presents selective antileishmanial effect, which is associated with multi-target action, and can be considered for future studies for the treatment against disease.


Assuntos
Aminoquinolinas/farmacologia , Antiprotozoários/farmacologia , Leishmania mexicana/efeitos dos fármacos , Triazóis/farmacologia , Aminoquinolinas/síntese química , Animais , Antiprotozoários/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Membrana Celular/química , Membrana Celular/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Macrófagos/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Organelas/efeitos dos fármacos , Fosfatidilserinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Triazóis/síntese química
12.
Nat Prod Res ; 35(21): 4192-4196, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32290698

RESUMO

Freshwater sponges can be considered a promising new source of bioactive compounds for the pharmaceutical industry; however, the research on their chemical composition is still in the incipient stage. We evaluated the most endemic Amazonian freshwater sponge species from the Drulia and Metania genera by untargeted metabolomic approaches, based on UHPCL-HRMS, in order to identify chemical markers and explore the diversity of specialized metabolites. The use of untargeted approaches allowed us to observe subsets of metabolites that enabled the characterization of, not only each genus, but also, of each species. Freshwater sponge species presented themselves as rich sources of fatty acids and sterols, which were putatively identified. These metabolites were suggested as chemical markers for further targeted metabolomic studies.


Assuntos
Água Doce , Poríferos , Animais , Ácidos Graxos , Metabolômica , Esteróis
13.
Anal Chem ; 91(18): 11747-11756, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31423767

RESUMO

Carbon isotope ratio (CIR) confirmation is one of the most complex and delicate analyses in the doping control field, due to the nature of the molecules to be confirmed, normally present in urinary samples as a consequence of an endogenous production. The requirements for method validation established by the World Anti-Doping Agency (WADA) have been pushing the accredited laboratories to improve their methods. The choice of the method is always a cost benefit ratio involving a hard-working and time-consuming analysis and the guarantee of reporting of reliable results. This work presents the method fully validated by the Brazilian Doping Control Laboratory as part of the preparation for the Rio de Janeiro Summer Olympic and Paralympic Games 2016. Sample preparation encompassed solid-phase extraction, liquid-liquid extraction, enzymatic hydrolysis, acetylation, and purification by preparative high-performance liquid chromatography, and analyses were performed by gas chromatography/combustion/isotope ratio mass spectrometry. This proved to be a robust method to CIR confirmation in a big event, as demonstrated by the analysis of 179 samples during the Games 2016, from clearly negative results and adverse findings for testosterone (T) and related substances, boldenone and its metabolite, 19-norandrosterone and formestane. Two atypical findings were also reported for T and metabolites.


Assuntos
Isótopos de Carbono/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Congêneres da Testosterona/urina , Acetilação , Brasil , Cromatografia Líquida de Alta Pressão , Estranos/urina , Humanos , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Extração em Fase Sólida , Esportes , Testosterona/análogos & derivados , Testosterona/urina
14.
Drug Test Anal ; 11(6): 772-781, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30636357

RESUMO

Erythropoiesis-stimulating agents (ESAs) have been used in horses for doping purposes to increase the performance of these animals in endurance sports. Currently, enzyme-linked immunosorbent assay (ELISA) and mass spectrometry methods are used to detect ESA abuse in equines. However, the sarcosyl polyacrylamide gel-electrophoresis (SAR-PAGE) technique could also be used, since its application in human doping control is well established and has proven to be more sensitive. In this work, the SAR-PAGE method was used to detect recombinant human erythropoietin (rHuEPO), novel erythropoiesis stimulating protein (NESP), continuous erythropoietin receptor activator (CERA), and fusion protein of erythropoietin with human immunoglobulin heavy chain Fc region (EPO-Fc) in horse blood and urine. The purification technique for human blood using MAIIA kits worked well for horse samples. The major challenge was horse urine immunopurification, which proved difficult due to filter clogging, but heating and cooling of the horse urine followed by filtration in 30-kDa molecular weight cut-off filters solved this problem. The limits of detection (LODs) of 1.3, 1.6, 6.6, and 13.3 pg/mL for rHuEPO, NESP, CERA, and EPO-Fc, respectively, obtained in spiked urine and 40, 100, 80, and 400 pg/mL for rHuEPO, NESP, CERA, and EPO-Fc, respectively, acquired in spiked blood are lower than the LODs reported in the literature using liquid chromatography-mass spectrometry (LC-MS) methods. In addition, the presence of ESAs was detected up to 9 days after the administration of microdoses of Hemax (rHuEPO), NESP, and CERA in horse blood and urine. SAR-PAGE may be implemented in the routine analysis of horse doping control laboratories for screening and confirmation of ESA abuse, mainly due to its high sensitivity for both matrices compared to published mass spectrometric methods.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Eritropoetina/sangue , Eritropoetina/urina , Cavalos/sangue , Cavalos/urina , Animais , Detergentes/química , Dopagem Esportivo , Masculino , Substâncias para Melhoria do Desempenho/sangue , Substâncias para Melhoria do Desempenho/urina , Sarcosina/análogos & derivados , Sarcosina/química , Detecção do Abuso de Substâncias/métodos
15.
Saudi Pharm J ; 26(3): 311-322, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29556122

RESUMO

Cancer is one of the biggest problems in public health worldwide. Plants have been shown important role in anticancer research. Viscum album L. (Santalaceae), commonly known as mistletoe, is a semi-parasitic plant that grows on different host trees. In complementary medicine, extracts from European mistletoe (Viscum album L.) have been used in the treatment of cancer. The study was conducted to identify chemical composition and antitumor potential of Viscum album tinctures. Chemical analysis performed by high resolution chromatography equipped with high resolution mass spectrometer identified caffeic acid, chlorogenic acid, sakuranetin, isosakuranetin, syringenin 4-O-glucoside, syringenin 4-O-apiosyl-glucoside, alangilignoside C and ligalbumoside A compounds. Some of these compounds are probably responsible for the reduction of tumoral cellular growth in a dose-dependent manner. It was observed that melanoma murine cells (B16F10) were more sensitive to V. album tinctures than human leukaemic cells (K562), besides non-tumoral cells (MA-104) had a much lower cytotoxicity to them. Apoptotic-like cells were observed under light microscopy and were confirmed by a typical DNA fragmentation pattern. Additionally, flow cytometry results using Annexin-V/FITC permitted to quantify increased expression of early and late apoptotic markers on tumoral cells, confirming augmented Sub G0 population, which was probably associated with a consistent decrease in G1, and an increase in S or G2/M populations. Results indicate the chemical composition of V. album tinctures influences the mechanisms of in vitro tumoral cell death, suggesting a potential use in cancer pharmacotherapy research.

16.
Drug Test Anal ; 9(11-12): 1685-1694, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28987069

RESUMO

One of the greatest challenges in anti-doping science is the large number of substances available and the difficulty in finding the best analytical targets to detect their misuse. Therefore, metabolism studies involving prohibited substances are fundamental. However, metabolism studies in humans could face an important ethical bottleneck, especially for non-approved substances. An emerging model for metabolism assessment is the zebrafish, due to its genetic similarities with humans. In the present study, the ability of adult zebrafish to produce metabolites of sibutramine and stanozolol, substances with a well-known metabolism that are widely used as doping agents in sports, was evaluated. They represent 2 of the most abused classes of doping agents, namely, stimulants and anabolic steroids. These are classes that have been receiving attention because of the upsurge of synthetic analogues, for which the side effects in humans have not been assessed. The samples collected from the zebrafish tank water were hydrolysed, extracted by solid-phase extraction, and analysed by liquid chromatography with high resolution mass spectrometry (LC-HRMS). Adult zebrafish could produce several sibutramine and stanozolol metabolites, including demethylated, hydroxylated, dehydroxylated, and reduced derivatives, all of which have already been detected in human urine. This study demonstrates that adult zebrafish can absorb, oxidise, and excrete several metabolites in a manner similar to humans. Therefore, adult zebrafish seem to be a very promising tool to study human-like metabolism when aiming to find analytical targets for doping control. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Dopagem Esportivo , Estanozolol/urina , Peixe-Zebra , Adulto , Animais , Cromatografia Líquida , Humanos , Hidroxilação , Extração em Fase Sólida , Estanozolol/química , Espectrometria de Massas em Tandem
17.
Drug Test Anal ; 9(11-12): 1658-1672, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29078043

RESUMO

This paper summarises the results obtained from the doping control analyses performed during the Summer XXXI Olympic Games (August 3-21, 2016) and the XV Paralympic Games (September 7-18, 2016). The analyses of all doping control samples were performed at the Brazilian Doping Control Laboratory (LBCD), a World Anti-Doping Agency (WADA)-accredited laboratory located in Rio de Janeiro, Brazil. A new facility at Rio de Janeiro Federal University (UFRJ) was built and fully operated by over 700 professionals, including Brazilian and international scientists, administrative staff, and volunteers. For the Olympic Games, 4913 samples were analysed. In 29 specimens, the presence of a prohibited substance was confirmed, resulting in adverse analytical findings (AAFs). For the Paralympic Games, 1687 samples were analysed, 12 of which were reported as AAFs. For both events, 82.8% of the samples were urine, and 17.2% were blood samples. In total, more than 31 000 analytical procedures were conducted. New WADA technical documents were fully implemented; consequently, state-of-the-art analytical toxicology instrumentation and strategies were applied during the Games, including different types of mass spectrometry (MS) analysers, peptide, and protein detection strategies, endogenous steroid profile measurements, and blood analysis. This enormous investment yielded one of the largest Olympic legacies in Brazil and South America. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Brasil , Humanos , Espectrometria de Massas , América do Sul
18.
Subst Use Misuse ; 49(9): 1098-114, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24766455

RESUMO

This article presents the prevalence of stimulant doping among Brazilian athletes, the analytical approaches used, as well as a general evolution of the detectability of the stimulants being used. Results from the Brazilian accredited doping control laboratory are compared with the global statistics disclosed by the World Anti-Doping Agency. The high prevalence of stimulant doping in Brazil can be attributed to several reasons, including "self-administration," a "body-shaping" culture, and the use of nutritional supplements.


Assuntos
Anfetaminas/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Cocaína/administração & dosagem , Dopagem Esportivo/estatística & dados numéricos , Detecção do Abuso de Substâncias/métodos , Atletas , Brasil , Humanos , Prevalência
19.
Bioanalysis ; 1(8): 1475-89, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21083096

RESUMO

Anabolic steroids are the main abused class of prohibited substances in doping control. These steroids are associated with enhancement of muscular mass and aggressiveness, resulting in increased performance. Chromatography and MS have a key role among methods developed to detect anabolic steroids in doping control laboratories. However, the classical analytical approach fails in detection of the so-called 'designer steroids'. This review focuses on the rise of tetrahydrogestrinone, a drug that became synonymous with designer steroids. The reasons why classical methods fail in tetrahydrogestrinone detection are discussed and how the detection was implemented is shown. Alternative strategies for detection of new drugs designed to cheat current analytical methodology are highlighted. Concern for the abuse of veterinary designer drugs and supplements is also acknowledged.


Assuntos
Anabolizantes/análise , Drogas Desenhadas/análise , Gestrinone/análogos & derivados , Detecção do Abuso de Substâncias/métodos , Drogas Veterinárias/análise , Técnicas de Química Analítica/métodos , Suplementos Nutricionais/análise , Dopagem Esportivo , Gestrinone/análise , Humanos
20.
J Chromatogr A ; 1150(1-2): 215-25, 2007 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16963059

RESUMO

Tetrahydrogestrinone, gestrinone and trenbolone are synthetic 19-norsteroids with androgenic properties sharing a labile conjugated ketotrienyl motif. Their LC-MS analyses tend to overcome classical derivatization problems, a shortcoming to the use of GC-MS. Therefore, alternative derivatization procedures were evaluated. The procedure with methoxylamine: pyridine followed by TMSImid: MSTFA gave the best results. This is attributed to the stability of the MO-TMS derivatives hindering the formation of artifacts and tautomerism. A full method is presented including SPE, hydrolysis and liquid-liquid extraction. It was possible to confirm the analytes below 2 ng/mL in urine, being the method robust and cost effective also for screening proposes.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Gestrinone/análogos & derivados , Gestrinone/urina , Acetato de Trembolona/urina , Adulto , Feminino , Gestrinone/análise , Gestrinone/química , Humanos , Estrutura Molecular , Reprodutibilidade dos Testes , Acetato de Trembolona/análise , Acetato de Trembolona/química
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