Analysis of multicomponent formulations containing pseudoephedrine HCl and chlorpheniramine maleate using first-derivative spectroscopy on a diode-array spectrophotometer.

Pseudoephedrine HCl and chlorpheniramine maleate are compounds which have overlapping UV spectra in solutions of phosphate buffer (pH 7.2), water, and 0.1 M HCl. The quantitation of both compounds was achieved by using first-derivative spectroscopy on a diode-array spectrophotometer. The application of this method for the analysis of content uniformity testing and measuring dissolution profiles was demonstrated.