Xanthene based resonance Rayleigh scattering and spectrofluorimetric probes for the determination of cyclobenzaprine: Application to content uniformity test

Abstract

In this work, a resonance Rayleigh scattering technique and a spectrofluorimetric technique were applied to the quantification of cyclobenzaprine through two validated methods. The suggested methods are based on a facile association complex formation between cyclobenzaprine and eosin Y reagent in the acidic medium. The resonance Rayleigh scattering method relied on the enhancement in the resonance Rayleigh scattering spectrum of eosin Y at 370 nm after the addition of cyclobenzaprine. On the other hand, the spectrofluorimetric quantification relied on the quenching effect of cyclobenzaprine on the fluorescence strength of the eosin Y reagent at 545 nm (excitation wavelength at 300 nm). The suggested methods were linear over the ranges of 0.07–1.75 μg/mL and 0.15–2.0 μg/mL with detection limit values of 0.023 μg/mL and 0.048 μg/mL for the resonance Rayleigh scattering method and the spectrofluorimetric method, respectively. All reaction conditions for cyclobenzaprine–eosin Y formation were experimentally evaluated and optimized. In addition, both methods were validated based on ICH rules. Furthermore, the developed methods were practically applied to the analysis of cyclobenzaprine in its commercial tablet dosage form with acceptable recoveries. Moreover, the content uniformity test of the commercial cyclobenzaprine tablets was successfully applied using the proposed spectroscopic methods based on USP rules.

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.…”

“…It is well known that some lipophilic basic drugs produce a quenching effect in the fluorescence strength of xanthene dyes. [ 9,17,23,27–29 ] Therefore, daclatasvir dihydrochloride (log P = 4.57 [ 30 ] ) can suppress the fluorescence strength of merbromin at 545 nm and can be quantitatively estimated through spectrofluorometric methodology (Figure 5).…”

Spectrofluorimetric determination of magnesium ions in water, ampoule, and suspension samples using a fluorescent azothiazol‐benzenesulfonamide derivative

“…Spectrofluorometric techniques have become a convenient analytical option because of their ability to deliver selectivity, and high sensitivity. [24,25] Among the most significant research topics in ecology and biochemistry are the development and the manufacture of novel sensors for the successful detection of metal ions. Fluorescence sensors have the advantages of high sensitivity, selectivity, and ease of use, and so are considered the excellent instrumental choice to detect metal ions.…”

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.…”