(1-Butyl-3-methylimidazolium Hexafluorophosphate) Based Sensor for Quantification of Eugenol Antioxidant

Synergistic effect of 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide and titanium oxide on the redox behaviour of flunarizine in solubilized media

Titanium oxide nanoparticles and 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide modified glassy carbon electrode (TiO₂/IL/GCE) has been fabricated for electrochemical sensing of flunarizine (FRH). The electrochemical properties and morphology of the prepared nanocomposite were studied by electrochemical impedance spectroscopy (EIS) and transmission electron microscopy (TEM). The response of the electrochemical sensor was found to be proportional to the concentrations of FRH in the range from 0.5 μgmL^-1 to 16 μgmL^-1. The detection limit obtained was 0.03 μgmL^-1. The proposed method was also applied to the determination of FRH in pharmaceutical formulation and human serum with good recoveries.

Electrochemical oxidation mechanism of eugenol on graphene modified carbon paste electrode and its analytical application to pharmaceutical analysis

Electrochemical properties of eugenol were investigated on a graphene modified carbon paste electrode (CPE) by using voltammetric methods, which exhibited a well-defined irreversible peak at about 0.7V vs Ag/AgCl, NaCl (3M) in Britton-Robinson buffer at pH 2.0. Mechanism of the electrochemical reaction of eugenol was studied by performing density functional theory (DFT) computations and mass spectroscopic analysis. (CPCM:water)-wB97XD/aug-cc-PVTZ//(CPCM:water)-wB97XD/6-31G(d) level calculations predicted that the formation of product P2, possessing a para-quinoid structure, is preferred rather than the product P1, suggested in the literature, having an ortho-quinoid system. Determination of eugenol in a pharmaceutical sample was realized in the light of the electrochemical findings, and a validated voltammetric method for quantitative analysis of eugenol in a pharmaceutical formulation was proposed. The differential pulse voltammogram (DPV) peak currents were found to be linear in the concentration range of 1.0 × 10^-7 to 1.7 × 10^-5M. The limit of detection (LOD) and the limit of quantification (LOQ) were obtained to be 7.0 × 10^-9 and 2.3 × 10^-8, respectively.