Quantitative approach to glucocorticosteroids analysis in human urine using LC-MS/MS

Abstract

Glicocorticosteroides estão incluídos na lista de substâncias proibidas da Agência Mundial Antidoping como analitos que dispensam quantificação. Entretanto, abordagens semiquantitativas são necessárias antes de relatar um resultado analítico adverso para essa classe de substâncias. Cromatografia líquida acoplada à espectrometria de massa (LC-MS) tem sido empregada com excelente seletividade e especificidade na análise de xenobiontes em misturas complexas. Foram analisadas amostras contendo glicocorticosteroides exógenos, a partir de diferentes vias de administração, utilizando o método proposto. Amostras geradas após administração sistêmica (via oral) apresentaram níveis de prednisolona ou prednisona superiores a 30 ng mL -1 , limite mínimo de desempenho requerido usado como parâmetro de diagnóstico. Por outro lado, vias não-sistêmicas parecem não apresentar biodisponibilidade para gerar um caso adverso em análises de controle de dopagem. Considerando o número reduzido de estudos similares na literatura, mais estudos de excreção podem ser realizados usando o método relatado com o objetivo de fornecer mais informações sobre o perfil de excreção de glicocorticosteroides administrados por vias sistêmicas e não sistêmicas.Glucocorticosteroids are included in the World Anti-Doping Agency (WADA) prohibited list as non-threshold analytes. Nevertheless, at least semi-quantitative approaches are necessary before reporting an adverse analytical finding for this class of substances. The liquid chromatography coupled to mass spectrometry (LC-MS) has been used with excellent selectivity and specificity in xenobiotic analysis in complex matrices. Real samples containing exogenous glucocorticosteroids from different administration routes were analyzed using the method proposed. Samples from systemic administration (oral route) presented levels of prednisolone or prednisone higher than 30 ng mL -1 , the minimum requirement performance level used as diagnostic parameter. On the other hand, non-systemic routes seem to not have bioavailability to generate an adverse case in doping control analysis. Considering the low number of similar studies available in the literature, more urinary studies could be done using the method reported aiming to provide more information about the excretion profile of glucocorticosteroids administered by systemic and non-systemic routes.

A highly sensitive method for the quantification of fludrocortisone in human plasma using ultra‐high‐performance liquid chromatography tandem mass spectrometry and its pharmacokinetic application

“…Very few reports were found in the literature on the direct estimation of fludrocortisone by LC‐MS/MS for bioequivalence studies. A literature survey revealed LC‐MS/MS methods for the determination of corticosteroids (glucorticocoids and mineralocorticoids) in human biological fluids (Taylor et al ., ), to determine doping agents in athletes that are used for anti‐inflammatory and pain relief actions (Soares et al ., ; Haneef et al ., ) and in animal tissues and urine (Chen et al ., ). These methods cannot be used for quantitative bioequivalence studies owing to their lack of sensitivity, matrix effects and high chromatographic run times.…”

Stochastic dynamic mass spectrometric quantification of steroids in mixture

“…We need to fill the gap of our knowledge whether the diffusion parameters (D ' SD ) obtained within the framework of the simpler model equation (5) correlate with the analyte concentration in solution. However, it must be taken into account for that there are already obtained excellent chemometric correlation coefficients between D SD -parameters according to equation (1) and the concentrations of steroids (1)-(3) in solution.…”

“…The same is true for the correlation between the D SD -data on steroid (4) and its chromatographic analysis with respect to the analyte concentration in solution shown in the next subsection. Because of, if the largest part of the chemometric correlation coefficients between the theory and experiment of a systematic quantitative analyses show that there is better chemometrics quantifying the concentration of the analytes according to equation (5) instead of equation 1, then we would revise the original assumption that only by means of equations (1) and (3) there can be gained excellent-to-exact quantification of the measurable variable intensity of ions of analytes, respectively, the analyte concentration in solution. The problem which currently prevents to determine unambiguously which of the model equations express the exact analyte concentration is the lack of enough data on quantitative relations.…”

Carbon isotopic characterization of prednisolone and prednisone pharmaceutical formulations: Implications in antidoping analysis

“…1 Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis is performed routinely to estimate the concentrations of prednisolone, prednisone, and their metabolites and to discriminate the forbidden administration routes from those allowed. [2][3][4][5] At urinary concentrations between the reporting level (30 ng/mL) and 60 ng/mL, WADA has recently recommended an additional GC-C-IRMS confirmatory analysis to determine their exogenous or endogenous origin. 6 Indeed, as reported widely in the literature, the non-sterile collection and transport conditions and the presence of normal or pathogen microbial flora in urine samples could lead to ex vivo degradation of endogenous compounds to banned substances.…”