RESUMEN
In 2017, higenamine was added to the World Antidoping Agency's (WADA) Prohibited list under group S3: beta-2 agonists and it is banned for athletes both in - and out of competition. Aim of this study was to characterize the urinary excretion profile of higenamine and its metabolite coclaurine after oral administration of multiple doses of higenamine capsules. For this purpose, an administration study including female basketball players was performed. For the detection of higenamine and cocalurine in the collected urine samples, a new, fast, and highly sensitive quantitative on-line SPE LC HRMS method was developed and validated. The method was applied for the quantification of higenamine and cocalurine in urine and their excretion pattern was defined. Results obtained show substantial inter-individual differences in the excretion profile of higenamine and coclaurine. For higenamine, half-lives were estimated to be between 4 and 27 h, and for coclaurine between 5 and 25 h. Furthermore, the data indicate that the elimination of coclaurine is rate-limited by its formation. Higenamine could be detected at a urine concentration above 10 ng/mL for at least 20 h after the last application for all study participants.
Asunto(s)
Alcaloides , Doping en los Deportes , Tetrahidroisoquinolinas , Humanos , Femenino , Tetrahidroisoquinolinas/orina , Alcaloides/orina , Administración Oral , Detección de Abuso de Sustancias/métodosRESUMEN
The detection of an intact ester of testosterone in plasma is leading towards unequivocal proof of the administration of exogenous testosterone. In the current study, a sensitive screening method for the detection of nine testosterone esters in human plasma was developed. By preparing oxime derivatives of intact testosterone esters, the sensitivity of the assay was increased. Furthermore, the method included liquid-liquid extraction (LLE) as sample clean-up, as well as online separation of the target analytes from the derivatization solution. The analysis was performed by liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS). The method developed herein is simple and rapid, and was validated according to World Anti-Doping Agency (WADA) guidelines.