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1.
Rapid Commun Mass Spectrom ; 35(17): e9141, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34106497

RESUMO

RATIONALE: The World Antidoping Agency (WADA) Monitoring program concentrates analytical data from the WADA Accredited Laboratories for substances which are not prohibited but whose potential misuse must be known. The WADA List of Monitoring substances is updated annually, where substances may be removed, introduced or transferred to the Prohibited List, depending on the prevalence of their use. Retroactive processing of old sample datafiles has the potential to create information for the prevalence of use of candidate substances for the Monitoring List in previous years. MetAlign is a freeware software with functionality to reduce the size of liquid chromatography (LC)/high-resolution (HR) full-scan (FS) mass spectrometry (MS) datafiles and to perform a fast search for the presence of substances in thousands of reduced datafiles. METHODS: Validation was performed to the search procedure of MetAlign applied to Anti-Doping Lab Qatar (ADLQ)-screened LC/HR-FS-MS reduced datafiles originated from antidoping samples for tramadol (TRA), ecdysterone (ECDY) and the ECDY metabolite 14-desoxyecdysterone (DESECDY) of the WADA Monitoring List. Searching parameters were related to combinations of accurate masses and retention times (RTs). RESULTS: MetAlign search validation criteria were based on the creation of correct identifications, false positives (FPs) and false negatives (FNs). The search for TRA in 7410 ADLQ routine LC/HR-FS-MS datafiles from the years 2017 to 2020 revealed no false identification (FPs and FNs) compared with the ADLQ WADA reports. ECDY and DESECDY were detected by MetAlign search in approximately 5% of the same cohort of antidoping samples. CONCLUSIONS: MetAlign is a powerful tool for the fast retroactive processing of old reduced datafiles collected in screening by LC/HR-FS-MS to reveal the prevalence of use of antidoping substances. The current study proposed the validation scheme of the MetAlign search procedure, to be implemented per individual substance in the WADA Monitoring program, for the elimination of FNs and FPs.


Assuntos
Anabolizantes/urina , Cromatografia Líquida/métodos , Dopagem Esportivo/métodos , Ecdisterona/urina , Espectrometria de Massas/métodos , Tramadol/urina , Dopagem Esportivo/prevenção & controle , Humanos , Urina/química
2.
J Pharm Biomed Anal ; 242: 116007, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367516

RESUMO

BACKGROUND: Dried blood spots have recently been approved by the World Anti-Doping Agency as an alternative biological matrix for testing of doping substances. However, their use is limited to the detection of non-threshold compounds without a Minimum Reporting Level due to the numerous issues related to quantitative analyses and the limitation on testing capabilities of a haemolysed matrix. AIM: In this study androstenedione, testosterone and IGF-1 were longitudinally monitored in four different blood matrices to evaluate the potential of liquid capillary blood as an alternative matrix for quantitative determination in doping control analysis. METHODOLOGY: The analytical protocols developed to pretreat 20 µL of the blood matrices selected were based: i) for testosterone and androstenedione, on supported liquid extraction for liquid blood matrices, and on ultrasonication in the presence of methanol for dried blood matrices; ii) for IGF-1, proteins precipitation followed by evaporation of the supernatant was used to pretreat both liquid and dried blood matrices. The detection for all the target analytes was performed using liquid chromatography coupled to mass spectrometry. The analytical workflows, once optimized, were fully validated according to the requirements of World Anti-Doping Agency and ISO 17025 standard and used for the analysis of venous (serum) and capillary (liquid plasma and dried whole blood collected using either volumetric or non-volumetric devices) blood samples collected from 7 healthy subjects. RESULTS: The validation results showed satisfactory performance as related to specificity, sensitivity, matrix effects, linearity, accuracy, and precision in all the blood matrices evaluated despite the limited volume of sample used. The analysis of the different blood matrices collected from the subjects showed non-significant differences between the levels of testosterone and androstenedione measured in dried (fixed volume collected) and liquid matrices. An acceptable underestimation (lower than 15 %) was observed in capillary plasma compared to venous serum. The testosterone/androstenedione ratio was similar in all the blood matrices considered (bias lower than 5 %), indicating this parameter was not affected by either the blood matrix or collection device selected. For IGF-1, the levels measured in liquid blood matrices differed significantly (bias higher than 20 %) from those measured in dried whole blood matrices, suggesting haemolyzed blood might represent a challenge for the determination of macromolecules, mainly due to the complexity of the whole blood matrix in comparison to plasma/serum. NOVELTY: The outcomes of our study suggest that liquid capillary blood might open new avenues to blood microsampling in doping control field. It represents an efficient alternative to overcome the issues related to venous blood and dried blood spot sampling. Furthermore, it also allows greater frequency of blood sampling, with minor discomfort and without needing a phlebotomist, for analyses that can only be performed in blood samples, with an increased probability to detect and report Adverse Analytical Finding.


Assuntos
Androstenodiona , Testosterona , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massa com Cromatografia Líquida , Fator de Crescimento Insulin-Like I , Espectrometria de Massas em Tandem/métodos , Congêneres da Testosterona , Teste em Amostras de Sangue Seco/métodos
3.
Bioanalysis ; 13(19): 1511-1527, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34617444

RESUMO

The summer Olympic Games is the major mega sports event since the first modern era Olympiad, held in Athens, Greece in 1896. International Olympic Committee (IOC) has the responsibility of the organization of the summer and winter Games ensuring the broadcast in all corners of earth. The World Anti-Doping Agency (WADA) is the responsible organization of the fight against doping in sports. IOC and WADA support the event's country WADA Accredited Laboratory to incorporate the maximum of the new analytical technologies to become applicable during the event's antidoping testing. The current study reviewed the last 5 years progresses of the antidoping system with emphasis on the laboratory field.


Assuntos
Técnicas de Química Analítica , Dopagem Esportivo/prevenção & controle , Humanos , Agências Internacionais , Laboratórios , Tóquio
4.
Toxins (Basel) ; 13(4)2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917988

RESUMO

Mycotoxins are naturally occurring food toxins worldwide that can cause serious health effects. The measurement of mycotoxin biomarkers in biological fluids is needed to assess individuals' exposure. The aim of this study was to investigate the incidence of mycotoxins in the Qatari population. Serum samples from 412 adults and urinary samples from 559 adults were analyzed for the presence of mycotoxin biomarkers. Multimycotoxin approaches have been applied, using liquid chromatography mass spectrometry methods. Samples were further analyzed for the oxidative stress markers and compared with regard to the incidence of mycotoxins. The presence of mycotoxins was identified in 37% of serum samples and in less than 20% of urine samples. It was found that 88% of positive of the samples were positive for only one mycotoxin, while 12% of positive samples had two or more mycotoxins. Trichothecenes and zearalenone metabolites were most commonly detected mycotoxins, followed by aflatoxins, roquefortine C and mycophenolic acid. The presence of mycotoxins was found to positively correlate with oxidative stress markers. The obtained results illustrate the importance of mycotoxin biomonitoring studies in humans and the need to elucidate the underlying mechanisms of mycotoxin-induced toxicity.


Assuntos
Monitoramento Biológico , Contaminação de Alimentos , Micotoxinas/sangue , Micotoxinas/urina , Estresse Oxidativo , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Carga Corporal (Radioterapia) , Cromatografia Líquida de Alta Pressão , Dano ao DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Catar , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
5.
Drug Test Anal ; 13(2): 460-465, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33119942

RESUMO

The current study examined the stability of several antidoping prohibited substances analytes in urine after 15-min exposure to UV-C light in a Biosafety Level 2 cabinet. The urine matrices were exposed within the original antidoping bottles with the aim to destroy DNA/RNA and possible SARS CoV-2. The analytes small molecules Phase I and Phase II metabolites and peptides, in total 444, endogenous, internal standards, and prohibited substances, pH, and specific gravity in urine were studied. The accredited analytical methods were used by Anti-Doping Laboratory Qatar for the comparison of data of the same urine samples analyzed with and without UV-C exposure. In the study conditions, no problems of stability were detected in the substances spiked in the urine samples exposed in the UV-C irradiation.


Assuntos
Anabolizantes/urina , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Contenção de Riscos Biológicos/métodos , Dopagem Esportivo , Humanos , Raios Ultravioleta
6.
Toxicon ; 171: 43-50, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31586556

RESUMO

Mycotoxins are secondary metabolites produced by different fungal spices and are found in diverse agricultural crops worldwide; they pose a severe threat to public health. Mycotoxins can cause either acute or chronic symptoms, depending on the type and dose of mycotoxin one has been exposed to. Thus, a continuous monitoring of mycotoxins is needed. Since the discovery of mycotoxins, numerous countries, including the Gulf Cooperation Council (GCC) countries, have established mycotoxin-specific regulations for feed and food. Although a number of studies in GCC countries have investigated the presence of mycotoxins, till date, there are no reviews focusing on the mycotoxin contamination of the food and feed from this region. This review is the first study to present an up-to-date overview of the occurrence of mycotoxins in feed and food in the GCC countries and to discuss the techniques used for mycotoxin analysis.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Análise de Alimentos/métodos , Oriente Médio
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