Use of aniline blue dye in the indirect spectrophotometric determination of metoclopramide in the presence potassium permangannte

A rapid and sensitive indirect spectrophotometric method was developed for determining metoclopramide hydrochloride in its pure form and pharmaceutical preparations. The method is based on the oxidation of metoclopramide by an excess of potassium permanganate, followed by the reaction of the unreacted oxidizing agent with aniline blue in an acidic medium of nitric acid. Measurements were taken at the maximum wavelength of 600 nm.

The method complies with the Beer-Lambert law within the concentration range of 1.0–22.5 µg/mL, with a molar absorptivity of8.32 ×10⁴ L/mol·cm. The accuracy of the method was determined to be 102.2%, while the precision was less than 0.82%.While the LOD and LOQ were0.075µg/ml and 0.252µg/ml. This method was successfully applied to the analysis of pharmaceutical preparations, including both injection and tablet forms.