Visible Spectrophotometric Methods for the Determination of Venlafaxine Hydrochloride and Ritodrine Hydrochloride in Pharmaceutical Formulations

Abstract

Simple and sensitive visible spectrophotometric methods have
been developed for the estimation of venlafaxine hydrochloride and
ritodrine hydrochloride. In the proposed methods the drugs react
with Folin-Ciocalteu reagent under alkaline conditions, which form
blue-coloured chromogens having absorption maxima at 740 nm
and 675 nm and obey Beer's law in the concentration ranges of
10-50  μg/mL and 2.5 to 12.5  μg/mL respectively. These methods
are extended to pharmaceutical preparations and there is no interference
from any common pharmaceutical additives and diluents.