European Journal of Biomedical and Pharmaceutical Sciences

SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF GUAIFENESIN AND PSEUDOEPHEDRINE HYDROCHLORIDE USING DERIVATIVE OF RATIO SPECTRA AND RATIO DIFFERENCE METHODS.

Khalid Abdel-Salam Attia, Mohammed Wafaa Nassar, Ahmed El-Olemy *

ABSTRACT

Two simple, accurate, precise, reproducible, requiring no prior separation and economical procedures have been developed for the simultaneous analysis of binary mixture of guaifenesin (GUI) and pseudoephedrine hydrochlorid (PSD). The first method is the derivative of ratio spectra, where the absorption spectra of each drug were divided by a suitable absorption spectrum of the interfering drug (divisor) and then the first derivative (for PSD) and second derivative (for GUI) of these ratio spectra were recorded. The second method is the ratio difference, where The difference in peak amplitudes between two selected wavelengths in the ratio spectra were recorded for each drug. Beer’s law was obeyed in the concentration ranges of 2-40 and 5-40 μg/ml for GUI and PSD respectively for both methods. The proposed methods were successfully applied for the determination of the two compounds in synthetic mixtures and in commercial drops.

Keywords: Guaifenesin; pseudoephedrine; derivative ratio; ratio difference.