Simultaneous Determination for Lansoprazole and Simvastatin drugs via Ultraviolet Spectrophotometry

Abstract

A semi-novel, accurate, sensitive, simple, requiring no prior separation and economical procedures have been developed for the simultaneous analysis of binary mixture of Lansoprazole (Lanso) and Simvastatin (Semva). The first method is the Derivative of ratio spectra, in which the absorption spectrum of one drug as interfering drug were subtracted from the absorption spectrum of the mixture and then the net spectrum derivative, the first derivative (for Lanso) and second derivative (for Semva). Beer’s law was obeyed in the concentration ranges of (1-90) and (4-70) μg.ml-1 and the results showed that the method was precise and accurate with RSD% of (0.0161-0.0235), (0.0360-0.0525) and R.E% (0.3125-0.4545), (-0.0909-0.0312) for Lanso and Semva respectively. The second method based on ratio difference, where the absorption spectrum of mixtures the drugs was divided by the on the absorption spectrum of a suitable the interfering drug. The difference in peak amplitudes between the two selected wavelengths in the ratio spectra were recorded for each drug. Beer’s law was obeyed in the concentration ranges of (0.1-30) and (1-40) μg.ml-1 and the results of the method were precise and accurate with RSD% of (0.2880-0.4580), (0.1294-0.9880) and R.E% of (-0.0090-0.0909), (-0.0651-0.0710) for Lanso and Semva respectively of this method.
 The proposed methods were successfully applied for the determination of the two compounds.