Quantitative study ternary mixture of paracetamol, ibuprofen and caffeine in solid pharmaceutical dosage forms by ratio ultraviolet spectroscopy

Abstract

This paper aims to apply ratio ultraviolet spectroscopy to determine the concentration of substances in a ternary mixture containing paracetamol (PA), ibuprofen (IBU), and caffeine (CA) without chemical treatment, the solvent used in the analysis is a mixture of ethanol with water friendly to environment and safety for users. The ratio ultraviolet spectroscopy method is based on the difference between the peak amplitude of the proportional spectrum at two wavelengths to build regression equations and analytical parameters. The two wavelengths selected in the ratio spectrum for PA, IBU, CA are 246 and 275 nm, 218 and 245 nm, 244 and 278 nm, respectively. The linear range for PA and IBU is 4-40 µg/ml, and for CA, it is 0.8-8 µg/ml; limit of detection (LOD) and limit of quantification (LOQ) of PA, IBU,
CA were 0.78, 1.18, 0.38 µg/ml and 2.37, 3.59, 1.17 µg/ml, respectively. The ratio ultraviolet spectroscopy method has successfully determined the concentrations of three substances in a mixture of laboratory and commercial drugs.