SIMULTANEOUS ESTIMATION OF DOXOFYLLINE AND AMBROXOL IN TABLET DOSAGE FORM BY REVERSE PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

A new, simple, accurate, linear, precise, efficient and reproducible Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) method for the simultaneous determination of Ambroxol and Doxofylline in combined tablet dosage form. The chromatographic method was standardized using a Kromosil C18, 150mm x 4.6 mm, 3.5 mu (particle size), Thermo scientific from Germany with isocratic conditions, and mobile phase containing potassium dihydrogen orthophosphate buffer-pH 6.8 (0.01M KH2PO4): acetonitrile (25: 75) at flow rate of 1ml/min using UV detection at 257 nm. The retention times of Ambroxol and Doxofylline were 5min and 2min, respectively. The method was linear over the concentration range for Ambroxol 0.6-36 mu g/mL and for Doxofylline 16-96 mu g/mL. The recovery of Ambroxol and Doxofylline was found to be in the range of 98.13-99.85% and 98.09-99.66%, respectively. The validation of method was carried out using ICH guidelines. The described HPLC method was successfully employed for the analysis of pharmaceutical formulations containing combined dosage form. From the comprehensive validation conducted, it was concluded that the method is stable and could be used throughout shelf life of the drug.