Development and Validation Of Spectrophotometric Methods For The Estimation of Oseltamivir Phosphate

Abstract

Oseltamivir phosphate (OP) is chemically ethyl (3R, 4R, 5S)-4-acetamino-5-amino-3-(ethylpropoxy)-1-carboxylate phosphate used to treat flu virus (influenza).The drug is commercially available as tablets for oral administration. In the present work two simple, economical, precise and accurate UV spectrophotometric methods have been developed for the estimation of oseltamivir phosphate in bulk and pharmaceutical formulation .Method A is absorption maxima method in which λmax was found to be 217.06nm. Method B is first order derivative spectroscopy where drug showed λmax at 214.35 nm. Amplitude (dA/dλ) was calculated and was plotted against concentration and regression equation was calculated. Linearity was observed in the concentration range 5-25µg/ml (r =0.999) for the two methods. The % assay for the marketed formulation for absorption maxima, first order derivative method was found to be 97.62%, 98.02% respectively. The methods were validated with respect to linearity, precision and accuracy studies. Recovery studies for absorption maxima, first order derivative was found to be 98.61%, 98.71%respectively. The methods were found to be simple, precise and accurate and can be employed for routine quality control analysis of oseltamivir phosphate in bulk as well as from its dosage form.