Spectrophotometric and High Performance Liquid Chromatographic Methods for Determination of Metoclopramide inPharmaceutical Preparations

A rapid, simple, and sensitive spectrophotometric and high performance liquid chromatographic methods have been developed for the quantitative determination of metoclopramide hydrochloride (MCP) in both pure and dosage forms. The spectrophotometric method is based on diazotization of (MCP) and then coupling with 2,4dihydroxyacetophenone in alkaline medium. The resulting azodye exhibits maximum absorption at 450 nm with a molar absorptivity of 2.48 X 10 l.mol.cm. Beer's law is obeyed over the range 10-300μg/25 ml, i.e., 0.4-12 ppm with a relative standard deviation (RSD)of better than±1.092% and relative error better than -1.1%. HPLC method has been developed for the measurement of (MCP), the analysis was achieved on a C8 column using acetonitrile, water, and methanol in the ratio of 40:50:10 (V:V:V) (in the presence of 1% of sodium acetate) as a mobile phase by isocratic elution at 1 ml/min. flow rate, and detection was done spectrophotometrically at 308 nm. A linear relationship is obeyed over the range 0.18-0.8 ppm with a relative standard deviation (RSD) of better than ±3.7% and relative error better than -1.6%. Both methods were applied successfully to the assay of (MCP) in pharmaceutical preparations in the form of syrup, injection, and tablet.