Simultaneous determination of dextromethorphan hydrobromide, doxylamine succinate and pseudoephedrine hydrochloride in cough and cold syrup by area under curve spectrophotometry method

Abstract

Dextromethorphan hydrobromide, doxylamine succinate and pseudoephedrine hydrochloride are in cough and cold formulation. The research aims to determine levels of dextromethorphan hydrobromide, doxylamine succinate and pseudoephedrine hydrochloride in their combined cough and cold syrup by the area under curve spectrophotometry method without a prior separation step. This method is based on the area under the curve value of each spectrum in various concentrations is calculated to selected wavelength range analysis, with ethanol as solvent. Then, this method was applied to determine levels of dextromethorphan hydrobromide, doxylamine succinate and pseudoephedrine hydrochloride in syrup. The result of this method is the analysis of selected wavelength ranges of dextromethorphan hydrobromide, doxylamine succinate and pseudoephedrine hydrochloride in the wavelength ranges of 273-283 nm, 262-272 nm and 251-261 nm, respectively. The area under curve method has linearity 0.9997, accuracy 100.61% and precision 0.40% for dextromethorphan hydrobromide, linearity 0.9980, accuracy 100.68% and precision 0.70% for doxylamine succinate, linearity 0.9991, accuracy 100.38% and precision 0.45% for pseudoephedrine hydrochloride. The method is successfully applied to determine dextromethorphan hydrobromide, doxylamine succinate and pseudoephedrine hydrochloride in cough and cold syrup simultaneously and fulfill the validation requirements.