A Rapid Isocratic HPLC Assay for Dipyridamole Using a Microbore Column Technique

Abstract

A simple, rapid and sensitive assay for the quantitation of dipyridamole in human plasma has been developed using a reversed-phase C18 microbore HPLC column. Dipyridamole and the internal standard (propranolol) were separated from the plasma by reversed-phase liquid chromatography following a direct plasma protein precipitation. For sample analysis 50 μl of the internal standard (propranolol 125 μg/ml) and 50 μl of perchloric acid (60% w/v) were added to the 500 μl of plasma. After brief vortex and centrifugation, the supernatant (100 μl) was injected onto the column. Chromatography was carried on a 5 μm ODS Hypersil C18 microbore column (2 mm I. D. × 10 cm) using an acetonitrile-water (48:52, v/v) mobile phase containing 20 mM Na₂HPO₄ and 50 mM sodium dodecyl sulfate adjusted to pH 2. The eluant was monitored at 305 nm. The run time for a plasma sample was less than 12 min. The intra- and inter-assay samples per day as the sample preparation is simple, required no extraction and the run time per sample is less than 12 min. The assay was proved to be suitable for the routine analysis in clinical and pharmacokinetic studies.