Quantification of GR90291 in human blood by high resolution gas chromatography—mass selective detection (HRGC-MSD)

A specific and sensitive high resolution gas chromatography—mass spectrometry method for the determination of GR90291 in human blood is described. The extraction of GR90291 from blood required a polar organic solvent mixture. The crude extract was further purified by successive liquid—liquid partitioning prior to esterification with an HCl—n-butanol solution. This derivative was analysed using a deuterium-labelled internal standard by selected ion monitoring mass spectrometry. The calibration curve ranged from 1 to 100 ng ml −1. The method is reliable for the determination of GR90291 pharmacokinetics in human subjects.