Chiral analysis of selected enantiomeric drugs relevant in doping controls

Upon screening identification of Stanozolol, GC/HRMS confirmation of the suspicious sample is done by reanalysis of the urine specimen, where a specific immunoaffinity purification procedure is used to selectively isolate the long term excreted metabolites of Stanozolol. By meeting the specific identification criteria for more than one metabolite of the same parent compound, additional evidence could be obtained in the decision making process in doping control.

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A Review of Analytical Methods for the Determination of Tibolone: Pharmacokinetics and Pharmaceutical Formulations Analysis and Application in Doping Control

Current Pharmaceutical Analysis ◽

10.2174/1573412916666191025143214 ◽

2020 ◽

Vol 17 (1) ◽

pp. 31-39

Author(s):

Marilene Lopes Ângelo ◽

Fernanda de Lima Moreira ◽

Ana Laura Araújo Santos ◽

Hérida Regina Nunes Salgado ◽

Magali Benjamim de Araújo

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Analytical Methods ◽

Estrogenic Activity ◽

Biological Fluids ◽

Pharmaceutical Formulations ◽

Doping Control ◽

Specific Effects ◽

In Doping

Background:: Tibolone is a synthetic steroid commercialized by Organon under the brand name Livial (Org OD14), which is used in hormone therapy for menopause management and treatment of postmenopausal osteoporosis. Tibolone is defined as a selective tissue estrogenic activity regulator (STEAR) demonstrating tissue-specific effects on several organs such as brain, breast, urogenital tract, endometrium, bone and cardiovascular system. Aims:: This work aims to (1) present an overview of important published literature on existing methods for the analysis of tibolone and/or its metabolites in pharmaceutical formulations and biological fluids and (2) to conduct a critical comparison of the analytical methods used in doping control, pharmacokinetics and pharmaceutical formulations analysis of tibolone and its metabolites. Results and conclusions: : The major analytical method described for the analysis of tibolone in pharmaceutical formulations is High Pressure Liquid Chromatography (HPLC) coupled with ultraviolet (UV) detection, while Liquid Chromatography (LC) or Gas Chromatography (GC) used in combination with Mass Spectrometry (MS) or tandem mass spectrometry (MS/MS) is employed for the analysis of tibolone and/or its metabolites in biological fluids.

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A New Approach for Approximate Solution of ADE: Physical-Based Modeling of Carriers in Doping Region

Mathematics ◽

10.3390/math9050458 ◽

2021 ◽

Vol 9 (5) ◽

pp. 458

Author(s):

Leobardo Hernandez-Gonzalez ◽

Jazmin Ramirez-Hernandez ◽

Oswaldo Ulises Juarez-Sandoval ◽

Miguel Angel Olivares-Robles ◽

Ramon Blanco Sanchez ◽

...

Keyword(s):

Differential Equation ◽

Approximate Solution ◽

Analytic Solution ◽

Order Differential Equation ◽

Electric Circuit ◽

New Approach ◽

In Doping ◽

Electric Behavior ◽

Spatio Temporal ◽

Physical Phenomena

The electric behavior in semiconductor devices is the result of the electric carriers’ injection and evacuation in the low doping region, N-. The carrier’s dynamic is determined by the ambipolar diffusion equation (ADE), which involves the main physical phenomena in the low doping region. The ADE does not have a direct analytic solution since it is a spatio-temporal second-order differential equation. The numerical solution is the most used, but is inadequate to be integrated into commercial electric circuit simulators. In this paper, an empiric approximation is proposed as the solution of the ADE. The proposed solution was validated using the final equations that were implemented in a simulator; the results were compared with the experimental results in each phase, obtaining a similarity in the current waveforms. Finally, an advantage of the proposed methodology is that the final expressions obtained can be easily implemented in commercial simulators.

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