VISIBLE SPECTROPHOTOMETRIC METHODS FOR ESTIMATION OF LANSOPRAZOLE IN PHARMACEUTICAL FORMULATION

Two simple and sensitive visible spectrophotometric methods have been developed and subsequently validated for the estimation of lansoprazole in bulk and pharmaceutical formulation. Method A is based on formation of greenish blue colored complex with ferric nitrate and potassium ferricyanide which exhibit absorption maximum at 713 nm and obeyed beer's law in the concentration range of 0.5 – 6 µg/mL. Method B is based on formation of orange-red colored complex with ferric nitrate and 2,2' bipyridyl which exhibit absorption maximum at 520 nm and obeyed Beer's law in the concentration range of 1 – 8 μg/mL. The results of analysis for both the methods have been validated statistically and by recovery studies. The proposed methods are sensitive, accurate, precise and economical for estimation of lansoprazole in bulk and pharmaceutical formulation.