Spectroscopic strategies for quantitation of varenicline in pharmaceutical preparations and content uniformity testing

Abstract

Herein, two new facile methods were examined for varenicline determination using erythrosine. The latter is a food additive that has been recently investigated as a fluorescent dye for the determination of drugs. In the first method, the fluorescence of erythrosine B was quenched quantitatively by increasing the concentration of varenicline through ion-pair complex formation. This linear response was a basis for the spectrofluorimetric method used for varenicline quantitation in pure and dosage forms. The quenching is correlated with the concentration linearly over the range of 0.4–4.0 µg ml −1 at 550 nm after excitation at 528 nm with a correlation coefficient of 0.9993. Different parameters were investigated to reach the optimal conditions with the highest sensitivity and repeatability. The second method is depending on measuring the formed complex by spectrophotometry at 550 nm over the range of 1.0–10.0 µg ml −1 with an excellent correlation coefficient of 0.9999. The suggested methods were validated consistently with ICH guidelines, with acceptable results. The procedures were used to test the uniformity of content of Champix tablets. By comparing with the previous spectroscopic method, there was no significant difference as revealed from the calculated Student t -test and variance ratio F -test values.

Green spectrophotometric and spectrofluorimetric determination of biperiden hydrochloride using erythrosine B sensing probe

“…The selection of water as a solvent also has many advantages such as being cheap, available, and green. The EB complex with drugs always shows maximum intensity in water rather than organic solvents as reported in various studies [14][15][16]19].…”

“…Therefore, at a weakly acidic medium (pH 4), the ion-pair complex between the tertiary amine-containing drug (BIP) and the reagent (EB) is formed due to electrostatic force between the tertiary amino group of BIP and phenate group of EB [32]. Various tertiary amine drugs have been documented to interact with EB, causing the inhibition of its inherent emission magnitude [15,16,30,33]. The proposed mechanism is presented in Figure 10.…”

“…It was found that the maximum absorbance was produced at pH 4 (Figure 4). Most studies of EB quenching by basic drugs proceed in the acidic medium [15][16][17][18]. Different volumes of BR buffer (0.3-2.0 mL) at pH 4 were examined.…”

Validated spectrofluorimetric and resonance Rayleigh scattering methods for determining naftidrofuryl in varied pharmaceutical samples based on its interaction with erythrosin B

“…Recently, xanthene dyes (eosin Y, erythrosin B, fluorescein, merbromin) have been used as colorimetric, fluorescent, and/or RRS analytical reagents for determining a wide range of active pharmaceutical ingredients [12]. For example, eosin Y and merbromin dyes have been reported for determining daclatasvir, cyclobenzaprine, fluvoxamine, atomoxetine, oxybutynin, dexlansoprazole and some β-blockers [13][14][15][16][17][18][19], while erythrosin B has been utilized for determining rupatadine, duloxetine, terbinafine, venlafaxine, nilotinib trospium, and varenicline [20][21][22][23][24][25][26]. The benefits of using erythrosin B include its low price and a high degree of stability.…”

Utility of the food colorant erythrosine B as an effective green probe for quantitation of the anticancer sunitinib. Application to pharmaceutical formulations and human plasma

“…The utilization of xanthene dyes as fluorometric reagents has been reported in the analysis of various pharmaceutical compounds [25][26][27][28][29][30][31][32][33][34]. The goal of this research is to study the interaction of EB with SUN.…”