Development and Validation Of RP-HPLC Method for Simulataneous Estimation Doxophyline and Montelukast Sodium in Tablet Dosage Form

A simple, rapid, accurate, precise and economical reverse phase high performance liquid chromato graphic method has been developed for simultaneous estimation of Doxophylline and Montelukast sodium. The separation of drugs was achieved on Inertsil Ph-3 column (250 mmx4.6 mm id, 5 μm particle size) with mobile phase of Ammonium acetate 0.05milimolar and Glacial acetic acid buffer (pH 3.5): Methanol (18:82 v/v) at flow rate of 1.2 ml/min. The detection was done at 274 nm and retention time was found to 4.4 mins and 8.4 mins for Doxophyline and Montelukast Sodium respectively. The run time for this method was 12 minutes. The validation was done as per ICH guideline. Doxophylline and Montelukast sodium showed a linear response in the concentration range of 15.99-47.98 μg/ml and 50.43-151.30 μg/ml respectively. The correlation co-efficient for Doxophylline and Montelukast sodium was found to be 0.9998 and 0.9999 respectively. The detection limit for Doxophylline and Montelukast was found to be 0.5 g/ml and 0.2 g/ml and quantitation limit 1.5g/ml and 0.6 g/ml respectively. The percentage recoveries obtained for Doxophylline and Montelukast sodium ranges from 101.4% to 100.3% and 100.0% to 101.5% respectively. This method can be successfully employed for routine analysis of both drugs in tablet dosage form.