Quantitative determination of olmesartan in human plasma and urine by liquid chromatography coupled to tandem mass spectrometry

A specific, sensitive and fast method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC–MS/MS) was developed for the determination of olmesartan in human plasma and urine. Solid-phase extraction (SPE) was used to isolate the compounds from biological matrix followed by injection of the extracts onto a C18 column with isocratic elution. The method was validated over the concentration range of 0.2–1000 and 5–10,000 ng/mL for olmesartan in human plasma and urine, respectively. The method was applied to the pharmacokinetic study of olmesartan medoxomil in healthy Chinese male and female subjects.