Simultaneous HPLC determination of alfuzosin, tamsulosin and vardenafil in human plasma and pharmaceutical formulations using time programmed fluorescence detection.

Alfuzosin and tamsulosin are recently co-administrated with vardenafil to treat symptoms of benign prostatic hyperplasia and erectile dysfunction. A highly sensitive and simple liquid chromatographic method was developed and validated for the simultaneous determination of the three drugs using moxifloxacin as an internal standard. Isocratic separation was achieved within 7.0 min using phenyl-hexyl column (250 × 4.6 mm i.d.) and a mobile phase composed of acetonitrile/0.25% phosphoric acid (30:70, v/v) at pH 3.0. The analysis was performed at a flow rate of 1.2 mL/min with fluorescence detection at 246/450 nm for Alfuzosin and vardenafil, and 226/322nm for tamsulosin using time programming technique. The proposed method was linear over the concentration ranges of 5.0-50.0ng/mL, 10.0-200.0ng/mL and 20.0-400.0ng/mL for alfuzosin, vardenafil and tamsulosin, with limits of detection of 0.56ng/mL, 0.98ng/mL and 2.81 ng/mL in a respective order. The developed method was successfully applied to determine the studied drugs in dosage forms and human plasma samples and the results were satisfactory as revealed by statistical analysis of the data.