Development of a method for the determination of vardenafil in human plasma by high performance liquid chromatography...

A simple high-performance liquid chromatographic (HPLC) method with photometric detection is described for the determination of vardenafil hydrochloride, a phosphodiesterase V inhibitor, in human plasma. Chromatographic separation of the analyte and internal standard was achieved on an analytical 250 x 4.6 mm i.d. reversed-phase Kromasil KR 100 C(18) (5 microm particle size) column using a mobile phase of acetonitrile-potassium dihydrogen phosphate (30:70 v/v). The run time was less than 15 min. Column eluate was monitored at 230 nm. The linearity over the concentration range of 10-1500 ng/mL for vardenafil was obtained and the limit of quantification (LOQ) was 10 ng/mL. The method has been applied to analysis of the vardenafil concentrations for application in pharmacokinetic studies.