ABSTRACT:
This work is concerned with the simultaneous determination of rabeprazole sodium (RAB) and ondansetron hydrochloride in combined pharmaceutical dosage form by two methods. The methods employ the application of simultaneous equation and graphical absorbance ratio (Q analysis) method. Both methods utilize methanol as a solvent .For simultaneous equation method RAB shows maximum absorbance at 284.20 nm and OND shows at 246.0 nm, where the linearity ranges for RAB and OND were 4-24 µg/ml and 2-14µg /ml, respectively.For absorbance ratio (Q analysis) method at Isobestic wavelength 234.2 nm and at 246.0 nm, the maximum absorption of OND, the linearity ranges for RAB and OND were 4-24 µg /ml and 2-14 µg /ml respectively. The accuracy of the methods was assessed by recovery studies and was found to be 100.60% ± 1.402 and 100.36% ± 1.645 for the simultaneous equation method, 99.56% ±0.09451 and 99.14% ± 0.3508 for the graphical absorbance ratio method for RAB and OND respectively .These methods are simple, accurate and rapid and they require no preliminary separation and can therefore be used for routine analysis of both drugs in laboratory prepared mixtures and in commercial pharmaceutical dosage form.