Optimization of LC Method for the Determination of Testosterone and Epitestosterone in Urine Samples for Biomedical and Anti-Doping Research

In 2011, researchers developed and validated a sensitive liquid chromatography (LC) method for the determination of testosterone (T) and epitestosterone (E) in human urine samples, with applications in biomedical and anti-doping research. The method involved solid-phase extraction (SPE) and was optimized for specificity, linearity, precision, and accuracy, with a limit of quantification for T and E at 2 ng mL-¹. The study included 116 healthy volunteers and 10 athletes, confirming the method's reliability in detecting T and E levels, as well as the T/E ratio, for potential doping. The LC method used UV detection and hydrophilic-lipophilic balance (HLB) cartridges for pre-concentration, showing good reproducibility and accuracy, with intra-day and day-to-day variability below 11.3%, and accuracies within 95.5-108.7%. The average T concentration in urine was 44±62 ng mL-¹, and for E, it was 33.00±47 ng mL-¹. The method proved to be fast, specific, precise, cost-effective, and accurate, suitable for clinical applications, prognosis of cancer treatment, and doping control.