Sensitive and rapid high‐performance liquid chromatography tandem mass spectrometry method for estimation of fulvestrant in rabbit plasma

A rapid and sensitive high‐performance liquid chromatography and electrospray tandem mass spectrometry method was developed and validated for estimation of fulvestrant in rabbit plasma using liquid–liquid extraction. The separation and quantification of fulvestrant were achieved by reverse‐phase chromatography on a Sunfire C₁₈ column (50 × 2.1. i.d., 3.5 μm) with isocratic elution at a flow rate of 300 μL/min using norethistrone as an internal standard from 500 μL plasma sample. The method was validated over the concentration range from 0.092 to 16.937 ng/mL with a lower limit of detection of 0.023 ng/mL. The intra‐day and inter‐day accuracy and precision were within 10%. The recovery was 85 and 90% for fulvestrant and norethistrone respectively. The chromatographic run time was only 2.5 min. Copyright © 2009 John Wiley & Sons, Ltd.