POLAROGRAPHIC-BEHAVIOR AND DETERMINATION OF RANITIDINE IN PHARMACEUTICAL FORMULATIONS AND URINE

A polarographic method for the determination of ranitidine is describe d, based on the reduction of the nitro group at a dropping-mercury ele ctrode. The proposed method permits the drug to be determined, without any prior separation or extraction, in pharmaceutical formulations an d urine at levels at which the unchanged drug is excreted. The current is diffusion controlled and proportional to concentration from 3.58 X 10(-3) to 1.50 mmol l(-1). The detection limit is 1.07 X 10(-3) mmol l(-1). The reduction process was studied at different pH values and a reduction mechanism is proposed in which the importance of the homogen eous chemical reactions associated with the electron-transfer steps ar e indicated.