Development and Validation of High Performance Liquid Chromatography Method for Simultaneous Estimation of Ambroxol and Doxofylline in Their Combined Tablet Dosage Form

The present study described a new, simple, accurate, and precise high performance liquid chromatography method for the simultaneous determination of Ambroxol and Doxofylline in combined tablet dosage form. The chromatographic method was standardized using a BDS hypersil C18, 250？mm × 4.6？mm, 5？μ (particle size), Thermo scientific from Germany with isocratic conditions, and mobile phase containing potassium dihydrogen orthophosphate buffer-pH 4.5 (0.05？M KH2PO4): acetonitrile (60？:？40) at flow rate of 1？ml/min using UV detection at 254？nm. The retention times of Ambroxol and Doxofylline were 3.510？min and 7.247？min, respectively. The method was linear over the concentration range for Ambroxol 3.75–11.25？μg/mL and for Doxofylline 50-150？μg/mL. The recovery of Ambroxol and Doxofylline was found to be in the range of 99.42–101.18% and 99.37–100.28%, 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. 1. Introduction Ambroxol is a secretolytic agent used in the treatment of tracheobronchitis, emphysema with bronchitis pneumoconiosis, chronic inflammatory pulmonary conditions, bronchiectasis, and bronchitis with bronchospasm asthma [1]. Chemically, it is trans-4-[(2-Amino-3,5-dibromobenzyl)amino]cyclohexanol hydrochloride [2]. Literature survey revealed that few spectroscopic methods RP-HPLC, HPTLC, and UPLC [3–10] methods have been reported for the estimation of Ambroxol with other drugs. Doxofylline is a new generation long acting oral methylxanthine derivative. Methylxanthines are phosphodiesterase inhibitors. It is mainly used for maintenance therapy in patients suffering from asthma and Chronic Obstructive Pulmonary Disease (COPD). Chemically, it is 7-(1,3-dioxolan-2-ylmethyl)-3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione [11]. Literature survey revealed that few spectrophotometric methods and RP-HPLC method have been reported for the estimation of Doxofylline with other drugs [12–15]. From the literature survey, it was found that many methods have been reported for estimation of Ambroxol and Doxofylline individually and in combination with other drugs, and no HPLC method for simultaneous estimation of Ambroxol and Doxofylline has been reported so far. Hence an attempt has been made to develop new HPLC method which is simple, rapid, reproducible, and economical method for simultaneous estimation of Ambroxol and Doxofylline in tablet dosage form. 2. Materials and Methods 2.1. Chemicals and Reagents