Approach of Spectral Resolution and Analyzing Spectral Purity for Quantification of Paracetamol and Flupirtine Maleate in Tablet Formulation

Abstract

The present research work was conducted to show the capabilities of the spectrophotometric approaches comparable to chromatographic techniques in terms of resolution, determination of spectral purity, and quantification of binary mixture present in tablet formulation. Overlapping spectra of the drugs paracetamol (PCM) and flupirtine maleate (FLU) present as a binary mixture were resolved using ratio subtraction plus the extended ratio subtraction (RS–ERS), method ratio subtraction method plus the unified constant subtraction (RS–UCS) method and ratio subtraction method plus the constant multiplication (RS–CM) method. After spectral resolution, each drug was quantified by measuring the absorbance at the respective wavelength maximum of the drug using a linear regression equation. The aforementioned three spectrophotometric approaches were initially applied to physical mixtures prepared in the laboratory; later it was extended to analyze marketed tablet formulation. The spectral purity of resolved spectra was studied by computing the spectral contrast angle (SCA) and the spectral ratio factor (SRF). Developed methods were validated as per the parameters mentioned under the International Council for Harmonization (ICH) guideline Q2 (R1). Developed methods were assigned greenness scores using the AGREE tool and successfully used for analyzing marketed tablet formulation.