A liquid chromatographic method for the determination of danazol in human serum

A liquid chromatographic method for the determination of danazol in human serum has been developed. Reversed-phase C8 and C18 columns were used with a column-switching valve, isocratic elution and UV detection. Sample pretreatment involved extraction of the drug with pentane-methylene chloride. The method enabled the measurement of the drug at a concentration as low as 1 ng ml-1, with precision of 15.0% and accuracy of 8.3%. The method was used to run a two way replicated pharmacokinetic study of danazol. The main pharmacokinetic parameters were (mean of two periods): AUCinf = 480.94 ng x h ml-1, Cmax = 53.2 ng ml-1, tmax = 2.5 h, t0.5 = 18.00 h.