Abstract

A simple, precise and rapid conductometric titration method for determination of phenylephrine-HCl in pharmaceutical formulations by using, bismuth (III) tetraiodide as precipitating agent has been described. The proposed method was based on the formation of ion-pair associate between PHE and the inorganic complex, bismuth (III) tetraiodide to form an orange- red precipitate with PHE and the conductance of the ion-pair solution was measured as a function of the volume of titrant. Different factors affecting the reaction have been evaluated to obtain the best results. The studied drug was evaluated in deionized water in the range of 0.4-2.5 mg (8-50 µg/ml) PHE. The results were in good agreement with those obtained by the reference method.

Keywords: Bismuth tetraiodide, conductometric titration, phenylephrine-HCl.