Resonance Rayleigh scattering and spectrofluorimetric approaches for the selective determination of rupatadine using erythrosin B as a probe: application to content uniformity test

Abstract

In this study, spectrofluorimetric and resonance Rayleigh scattering techniques were applied for the first time for determination of rupatadine through two validated methods. The proposed methods were based on a facile association complex formation between rupatadine and erythrosin B reagent in acidic medium. Spectrofluorimetric determination relied on the quenching effect of rupatadine on the fluorescence intensity of erythrosin B at 556 nm (excitation = 530 nm). Conversely, the resonance Rayleigh scattering (RRS) method relied on enhancement in the resonance Rayleigh scattering spectrum of erythrosin B at 344 nm after the addition of rupatadine. The developed methods produced linear results over ranges 0.15−2.0 μg/ml and 0.1−1.5 μg/ml, with detection limits of 0.030 μg/ml and 0.018 μg/ml for the spectrofluorimetric method and the RRS method, respectively. All reaction conditions for rupatadine–erythrosin B formation were optimized experimentally and both methods were validated according to International Council for Harmonisation guidelines. The developed methods were applied to estimate rupatadine content in its pharmaceutical tablet dosage form with acceptable recoveries. Furthermore, a content uniformity test for the commercial rupatadine tablets was successfully applied by the suggested spectroscopic methods according to United States Pharmacopeia guidelines.

Applying different spectroscopic techniques for the selective determination of daclatasvir using merbromin as a probe: Applications on pharmaceutical analysis

“…Also, this interaction led to a considerable intensification in the RRS spectrum of the xanthene dye in many cases. [ 22–25 ] This augmentation in the RRS of the merbromin spectrum may be related to the formation of a hydrophobic interface that is directly proportional to the RRS signal. [ 26 ] The formation of a hydrophobic interface can be explained by the interaction of daclatasvir dihydrochloride [existing as a protonated cation (water‐soluble ions)] with merbromin [existing as anions (water‐soluble ions)] to produce a binary complex (the neutral form) that generates a hydrophobic liquid–solid interface.…”

A green spectrofluorimetric approach for the versatile determination of Bilastine in real human plasma and pharmaceutical preparations with content uniformity testing

“…the proportion of active elements in the tablet formulation does not go beyond 25% of the entire weight of the tablet or if the content of the active constituent is less than 25 mg, it is advised that the CU of the tablet units should be investigated [22,25,26]. For the rst time, the spectro uorometric method was utilized to track the CU of BIL in commercial tablets.…”

A novel spectrofluorimetric method based on a reaction with an azoisoxazoles–benzenesulfonamide derivative for determination of uranium (VI) ions in water samples

“…The spectrofluorometric technique provides the merits of sensitivity, simplicity, laboratory availability, rapidity, selectivity, and low cost for quantitation of metals. [12][13][14][15][16][17] Fluorescence methodology has emerged as the most promising approach for U(VI) ions detection due to its comparatively simple, quick, and affordable. [18] The fluorometric process is rapidly becoming one of the most prominent U(VI) ion monitoring methods due to its higher sensitivity and superior selectivity when compared with the colorimetry approach using UV-vis spectrophotometers.…”