High-performance liquid chromatographic determination of papaverine in whole blood

The development and application of an assay method for papaverine in whole blood is reported. A single, simple extraction procedure at pH 10.0 using chloroform—n-hexane (2:3) as the solvent, results in pure extracts which can be chromatographed without further purification. Chromatography is performed on a nitrile-bonded phase, using n-hexane—dichloromethane—acetonitrile—propylamine (50:25:25:0.1) as mobile phase. This method is characterized by a between-day precision of 4% at the 200 ng/ml level and a detection limit of 5 ng/ml, and was successfully applied in a pharmacokinetic study.