Determination of Metoclopramide Hydrochloride in Pharmaceutical Formulations Using Three Different Spectrophotometric Methods

Three simple, selective, accurate and precise spectrophotometric methods were developed for the determination of Metoclopramide Hydrochloride (MCP) in dosage forms. The first method (Method A) is based on coupling reaction of diazotized MCP with 2,5-diphenyl-2,4-dihydro-pyrazol-3-one (DPP) in alkaline medium to form azo dye. The second method (Method B) is based on Schiff’s base formation reaction between MCP and 4-hydroxybenzaldehyde (HBD). The last method (Method C) is based on the formation of colored ion–pair complex from the reaction of MCP with Eosin Y (ESN). Beer’s law was obeyed in the concentration range of 1.35-40.37, 1.01-5.05 and 1.01-10.09 μg/mL MCP at 426, 386 and 543 nm with molar absorptivity of 1.51×104 L mol-1 cm-1, 2.10×104 L mol-1 cm-1 and 3.34×104 L mol-1 cm-1 for Method A, Method B and Method C, respectively. The proposed methods were successfully applied to the determination of MCP in pharmaceutical preparations without any interference from common excipients.