Determination of domperidone in human plasma using high performance liquid chromatography with fluorescence detection...

A simple and reliable method for the determination of domperidone in human plasma has been developed. Plasma samples (1mL) were pre-purified by a solid-phase extraction with Bond Elut(®) C18. The separation was achieved with XBridge™ C18 column (150mm×4.6mm i.d., 5μm) at 40°C. The mobile phase was a mixture of acetonitrile and 10mM ammonium acetate buffer (36:64, v/v), adjusted to pH 9.4 with 20% ammonium solution at a flow rate of 1.0mL/min. The peak was detected using fluorescence detector at excitation 282nm and emission 328nm. Retention times for domperidone and internal standard (propranolol) were 8.3min and 11.2min, respectively. The method showed a good linearity (r>0.999), precision (relative standard deviations <10.6%), and extraction recovery (85.7-99.7%) over a concentration of 1-100ng/mL. The lower limit of quantification (LLOQ) was 1.0ng/mL. This proposed method was successfully applied to a pharmacokinetic interaction study of domperidone in healthy Japanese volunteers.