Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
JACS Au ; 1(6): 750-765, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34254058

RESUMO

Rising population density and global mobility are among the reasons why pathogens such as SARS-CoV-2, the virus that causes COVID-19, spread so rapidly across the globe. The policy response to such pandemics will always have to include accurate monitoring of the spread, as this provides one of the few alternatives to total lockdown. However, COVID-19 diagnosis is currently performed almost exclusively by reverse transcription polymerase chain reaction (RT-PCR). Although this is efficient, automatable, and acceptably cheap, reliance on one type of technology comes with serious caveats, as illustrated by recurring reagent and test shortages. We therefore developed an alternative diagnostic test that detects proteolytically digested SARS-CoV-2 proteins using mass spectrometry (MS). We established the Cov-MS consortium, consisting of 15 academic laboratories and several industrial partners to increase applicability, accessibility, sensitivity, and robustness of this kind of SARS-CoV-2 detection. This, in turn, gave rise to the Cov-MS Digital Incubator that allows other laboratories to join the effort, navigate, and share their optimizations and translate the assay into their clinic. As this test relies on viral proteins instead of RNA, it provides an orthogonal and complementary approach to RT-PCR using other reagents that are relatively inexpensive and widely available, as well as orthogonally skilled personnel and different instruments. Data are available via ProteomeXchange with identifier PXD022550.

2.
J Anal Toxicol ; 45(7): 666-678, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-33025016

RESUMO

Stimulants are often used to treat attention deficit disorders and nasal congestion. As they can be misused and overdosed, the detection of stimulants is relevant in the toxicological field as well as in the doping control field. The effects of stimulants can indeed be beneficial for athletes. Therefore, their in-competition use is prohibited by the World Anti-Doping Agency (WADA). As stimulants represent one of the most detected categories of prohibited substances, automation of methods to detect and confirm their presence is desirable. Previous work has shown the advantages of using turbulent flow online solid-phase extraction liquid chromatography-tandem mass spectrometry (online SPE LC-MS-MS) for the detection and confirmation of diuretics and masking agents. Hence, a turbulent flow online SPE LC-MS-MS method, compliant with the WADA's identification criteria, was developed and validated for the detection and confirmation of 80 stimulants or metabolites with limits of identification varying between 10 (or possibly lower) and 100 ng/mL. As several metabolites are common metabolites for multiple administered stimulants, this means that with this method, misuse of well over 100 compounds can be detected. As the developed method uses the same columns and mobile phases as our turbulent flow online SPE LC-MS-MS method for the confirmation of diuretics and masking agents, there is no need to change the configuration of the instrument when switching between the diuretics method and the developed stimulants method.


Assuntos
Estimulantes do Sistema Nervoso Central , Dopagem Esportivo , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Extração em Fase Sólida , Espectrometria de Massas em Tandem
3.
Biomed Chromatogr ; 35(2): e4970, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32840903

RESUMO

As hypoxia-inducible factor stabilizers (HIFs) can artificially enhance an athlete's erythropoiesis, the World Anti-Doping Agency prohibits their use at all times. Every urine sample for doping control analysis has to be evaluated for the presence of HIFs and therefore sensitive methods that allow high sample throughput are needed. Samples suspicious for the presence of HIFs need to be confirmed following the identification criteria established by the World Anti-Doping Agency. Previous work has shown the advantages of using turbulent flow online solid-phase extraction (SPE) procedures to reduce matrix effects and retention time shifts. Furthermore, the use of online SPE allows for automation and high sample throughput. Both an initial testing procedure (ITP) and a confirmation method were developed and validated, using online SPE liquid chromatography-tandem mass spectrometry (LC-MS/MS), with limits of detection between 0.1 ng/ml (or possibly lower) and 4 ng/ml (or higher for GSK360a) and limits of identification between 0.1 ng/ml (or possibly lower) and 1.17 ng/ml. The ITP only takes 6.5 min per sample. To the best of our knowledge, these are the first ITP and confirmation methods that include more than three HIFs without the need for manual sample preparation.


Assuntos
Dopagem Esportivo , Fator 1 Induzível por Hipóxia/química , Pirazóis/urina , Detecção do Abuso de Substâncias/métodos , Triazóis/urina , Cromatografia Líquida/métodos , Glicina/análogos & derivados , Glicina/química , Glicina/urina , Humanos , Isoquinolinas/química , Isoquinolinas/urina , Limite de Detecção , Modelos Lineares , Pirazóis/química , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Triazóis/química
5.
J Chromatogr A ; 1624: 461231, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540072

RESUMO

Detection of endogenous anabolic androgenic steroids (EAAS) misuse is a major challenge in doping control analysis. Currently, a number of endogenous steroids, which constitute the steroid profile, are quantified using gas chromatography (GC). With this methodology, only the sum of the free and glucuronidated steroids is measured together. A dilute-and-shoot LC-MS method, which is compliant with the quality requirements for measuring EAAS established by the World Anti-Doping Agency (WADA), was developed and validated containing glucuronidated and sulfated steroids in order to gain some extra information and to expand the existing steroid profile. The developed method is, to the best of our knowledge, the first method to combine both steroid glucuronides and sulfates, which is compliant with the quality standards of the technical document on EAAS, established by WADA. The first advantage of this new steroid profile is the reduced sample preparation time, as it is a direct injection method of diluted urine. A second advantage is the ability of the used gradient to separate 5α-androstane-3α,17ß-diol-3-glucuronide (5ααßdiol3G), 5α-androstane-3α,17ß-diol-17-glucuronide (5ααßdiol17G), 5ß-androstane-3α,17ß-diol-3-glucuronide (5ßαßdiol3G) and 5ß-androstane-3α,17ß-diol-17-glucuronide (5ßαßdiol17G) allowing to gain specific information on these isomers, which cannot be accomplished in GC-MS screening due to hydrolysis. This steroid profile also contains free testosterone, 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione as markers of degradation. In total, 17 compounds and 10 isotopically labelled internal standards are included in this method.


Assuntos
Esteroides/urina , Cromatografia Líquida de Alta Pressão , Dopagem Esportivo , Glucuronídeos/análise , Glucuronídeos/química , Glucuronídeos/urina , Humanos , Espectrometria de Massas , Esteroides/química
6.
J Chromatogr A ; 1579: 31-40, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30430987

RESUMO

Diuretics can be misused to force diuresis to achieve weight loss or to mask the intake of a prohibited substance and are therefore prohibited by the World Anti-Doping Agency (WADA). For similar reasons other masking agents (vaptans, probenecid, etc.) are also prohibited by the WADA. The currently employed methods to detect diuretics in urine use extraction or dilute-and-shoot, combined with 1D- liquid chromatography (LC) high resolution mass spectrometry (MS) or LC-triple quadrupole MS. Dilute-and-shoot methods save time and work, but these methods encounter some problems (e.g., peak drift and matrix effect). Therefore, a 2D-LC-MS/MS application was developed, validated and evaluated as an alternative. The effect of a turbulent flow rate was studied by loading samples under different conditions and the turbulent flow rate was found to be more effective in removing matrix interferences. A correlation with the specific gravity was observed. A turbulent flow online solid phase extraction (SPE) method combined with LC-MS/MS for the detection of 50 diuretics and masking agents was developed and validated for identification purposes. This method combines the advantages of dilute-and-shoot while solving the issues of matrix effect and retention time shift. Furthermore, the presented method is compliant with WADA's identification criteria and can hence be used for screening and/or confirmation.


Assuntos
Cromatografia Líquida , Diuréticos/urina , Extração em Fase Sólida , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem , Dopagem Esportivo/prevenção & controle , Humanos
7.
Drug Test Anal ; 9(5): 699-712, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27497113

RESUMO

Urine collection containers used in the doping control collection procedure do not provide a protective environment for urine, against degradation by microorganisms and proteolytic enzymes. An in-house chemical stabilization mixture was developed to tackle urine degradation problems encountered in human sport samples, in cases of microbial contamination or proteolytic activity. The mixture consists of antimicrobial substances and protease inhibitors for the simultaneous inactivation of a wide range of proteolytic enzymes. It has already been tested in lab-scale, as part of World Anti-Doping Agency's (WADA) funded research project, in terms of efficiency against microbial and proteolytic activity. The present work, funded also by WADA, is a follow-up study on the improvement of chemical stabilization mixture composition, application mode and limitation of interferences, using pilot urine collection containers, spray-coated in their internal surface with the chemical stabilization mixture. Urine in plastic stabilized collection containers have been gone through various incubation cycles to test for stabilization efficiency and analytical matrix interferences by three WADA accredited Laboratories (Athens, Ghent, and Rome). The spray-coated chemical stabilization mixture was tested against microorganism elimination and steroid glucuronide degradation, as well as enzymatic breakdown of proteins, such as intact hCG, recombinant erythropoietin and small peptides (GHRPs, ipamorelin), induced by proteolytic enzymes. Potential analytical interferences, observed in the presence of spray-coated chemical stabilization mixture, were recorded using routine screening procedures. The results of the current study support the application of the spray-coated plastic urine container, in the doping control collection procedure. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Manejo de Espécimes/métodos , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Urina/química , Gonadotropina Coriônica/urina , DNA/urina , Dopagem Esportivo , Eritropoetina/urina , Seguimentos , Humanos , Peptídeos/urina , Projetos Piloto , Proteólise , Proteínas Recombinantes/urina , Manejo de Espécimes/instrumentação , Esteroides/urina , Detecção do Abuso de Substâncias/instrumentação , Urinálise/instrumentação , Urina/microbiologia
8.
Int J Mol Sci ; 17(10)2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27706103

RESUMO

SR9009 and SR9011 are attractive as performance-enhancing substances due to their REV-ERB agonist effects and thus circadian rhythm modulation activity. Although no pharmaceutical preparations are available yet, illicit use of SR9009 and SR9011 for doping purposes can be anticipated, especially since SR9009 is marketed in illicit products. Therefore, the aim was to identify potential diagnostic metabolites via in vitro metabolic studies to ensure effective (doping) control. The presence of SR9009 could be demonstrated in a black market product purchased over the Internet. Via human liver microsomal metabolic assays, eight metabolites were detected for SR9009 and fourteen metabolites for SR9011 by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Structure elucidation was performed for all metabolites by LC-HRMS product ion scans in both positive and negative ionization mode. Retrospective data analysis was applied to 1511 doping control samples previously analyzed by a full-scan LC-HRMS screening method to verify the presence of SR9009, SR9011 and their metabolites. So far, the presence of neither the parent compound nor the metabolites could be detected in routine urine samples. However, to further discourage use of these potentially harmful compounds, incorporation of SR9009 and SR9011 into screening methods is highly recommended.


Assuntos
Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/agonistas , Pirrolidinas/metabolismo , Tiofenos/metabolismo , Cromatografia Líquida de Alta Pressão , Dopagem Esportivo , Humanos , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Pirrolidinas/análise , Estudos Retrospectivos , Espectrometria de Massas em Tandem , Tiofenos/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA