UV-Spectrophotometry and first order derivative spectrophotometry methods for determination of rabeprazole sodium in bulk and tablets

Two simple, rapid, sensitive and accurate UVspectrophotometry (method I) and First order derivative (method II) have been developed for estimation of rabeprazole sodium in bulk and tablets. In (10% v/v) acetonitrile, the λmax of rabeprazole sodium was found to be 284 nm. The same spectrum was derivatised into first order derivative at Δλ = 2 and amplitude of the trough was recorded at 298 nm. In both the proposed methods, linearity was observed in the concentration range 4-28 μg/ml. The assay results were found to be in good agreement with label claim. The methods were validated statistically and by recovery studies.