SEPARATION, IDENTIFICATION AND QUANTITATIVE-ANALYSIS OF SUBSTITUTED BENZAMIDES IN PHARMACEUTICAL DOSAGE FORMS BY HIGH-PRESSURE LIQUID-CHROMATOGRAPHY

Reverse phase high pressure liquid chromatography has been used to separate, identify and analyse five closely structurally related benzamides: procainamide, sultopride, tiapride, sulpiride and metoclopramide. The influence of various parameters on the separation (solvent composition, pH, type and concentration of the anion modifying the ionic strength of the buffer) has been examined. The results of this study suggest that the separation mode is similar to an ion pair partition chromatography in which the nature of the counter-ion is essential. The method has been applied successfully to the quantitative analysis of some of the above mentioned compounds in pharmaceutical dosage forms. © 1979.