Electrocatalytic oxidation and nanomolar determination of guanine at the surface of a molybdenum (VI) complex-TiO2 nanoparticle modified carbon paste electrode

Mazloum Ardakani, M ; Sharif University of Technology | 2008

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  1. Type of Document: Article
  2. DOI: 10.1016/j.jelechem.2008.07.027
  3. Publisher: Elsevier , 2008
  4. Abstract:
  5. A modified carbon paste electrode was prepared by incorporating TiO2 nanoparticles with bis[bis(salicylidene-1,4-phenylenediamine)molybdenum(VI)]. A mixture of fine graphite powder with 4 wt% of TiO2 nanoparticles was applied for the preparation of the carbon paste (by dispersing in paraffin) and finally modified with a molybdenum (VI) complex. The electrocatalytic oxidation of guanine (G) was investigated on the surface of the molybdenum (VI) complex-TiO2 nanoparticle modified carbon paste electrode (MCTNMCPE) using cyclic voltammetry (CV), differential pulse voltammetry (DPV), chronoamperometry (CHA) and chronocoloumetry (CHC). Using the modified electrode, the kinetics of G electrooxidation were considerably enhanced by lowering the anodic overpotential through a catalytic fashion. The mechanism of G electrochemical behavior at the modified electrode surface was analyzed by various electrochemical methods. The prepared modified electrode showed voltammetric responses with high sensitivity for G, making it very suitable for the detection of G at nanomolar levels. A linear dynamic range of 7.0-200 nM for G was obtained in buffered solutions with pH 5.0. The detection limit was 3.4 nM. © 2008 Elsevier B.V. All rights reserved
  6. Keywords:
  7. Carbon ; Chemical oxygen demand ; Chronoamperometry ; Cyclic voltammetry ; Electrocatalysis ; Electrodes ; Electrolysis ; Electrooxidation ; Graphite ; Molybdenum ; Molybdenum compounds ; Nanoparticles ; Nanostructured materials ; Nanostructures ; Oxidation ; Paraffin waxes ; Paraffins ; Positive ions ; Vegetation ; Voltammetry ; Buffered solutions ; Carbon pastes ; Detection limits ; Differential pulse voltammetries ; Electrocatalytic oxidations ; Electrochemical behaviors ; ELectrochemical methods ; Graphite powders ; Guanine ; Guanines (g) ; High sensitivities ; Linear dynamic ranges ; Modified carbon paste electrodes ; Modified electrode ; Modified electrodes ; Nanomolar levels ; Overpotential ; Voltammetric responses ; Electrochemical electrodes
  8. Source: Journal of Electroanalytical Chemistry ; Volume 624, Issue 1-2 , 2008 , Pages 73-78 ; 15726657 (ISSN)
  9. URL: https://www.sciencedirect.com/science/article/abs/pii/S0022072808003045