Development and validation of a RP-HPLC method for the simultaneous estimation of sulfadoxine and pyrimethamine in combined dosage tablets

Abstract

A new simple, sensitive and reproducible RP-HPLC method for the simultaneous estimation of sulfadoxine and pyrimethamine in pharmaceutical formulations was developed and validated. The separation was carried out on Zorbax Eclipse Plus C18, 3.5 µm (4.6×100 mm) column with acetonitrile: 20 mM sodium acetate buffer pH 6, 80:20% v/v as the mobile phase at the flow rate of 1 ml/min. The eluent detection was carried out using UV-Visible PDA detector at 224 nm. The retention time of sulfadoxine and pyrimethamine was 0.9 min and 1.2 min respectively. Linearity was observed for sulfadoxine and pyrimethamine in the concentration range of 60-200 µg/ml and 3-10 µg/ml respectively. The recovery of sulfadoxine and pyrimethamine was found to be 97.21-98.56% and 96.90-97.26% respectively.