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


Yıldız G., AYDOGMUS Z., Çınar M., Senkal F., Ozturk T.

TALANTA, vol.173, pp.1-8, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 173
  • Publication Date: 2017
  • Doi Number: 10.1016/j.talanta.2017.05.056
  • Journal Name: TALANTA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1-8
  • Istanbul Technical University Affiliated: Yes

Abstract

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 0.7 V vs Ag/AgCl, NaCl (3 M) 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 x 10(-7) to 1.7 x 10(-8) M. The limit of detection (LOD) and the limit of quantification (LOQ) were obtained to be 7.0 x 10(-9) and 2.3 x 10(-8), respectively.