Voltammetric and impedance studies of inosine-5′-monophosphate and hypoxanthine

Abstract

The oxidation mechanism and adsorption of inosine 5V -monophosphate and hypoxanthine were investigated in solutions of different pH using voltammetric and impedance methods at glassy carbon electrodes. For both compounds, the pH dependence from differential pulse voltammetry showed that the same number of electrons and protons are involved in the rate-determining step of the electrochemical reaction. In the case of hypoxanthine, it was also possible to study the effect of different concentrations. At high concentrations of hypoxanthine, two oxidation peaks were observed, the first due to hypoxanthine oxidation with formation of oligomers and the second due to hypoxanthine oligomer oxidation, both compounds adsorbing strongly. Impedance measurements corroborated the voltammetric results and enabled the study of the adsorption of hypoxanthine on glassy carbon. D

Polymer-Bioglass Composite Coatings: A Promising Alternative For Advanced Biomedical Implants

“…Consequently, the charge transfer resistance increased. A similar behavior was observed for other biological compounds when adsorbed on glassy carbon electrodes (Oliveira Brett, 2002, 2003Brett, 1994).…”

“…The physiological fluids influence upon different coatings was investigated by electrochemical methods, largely spread nowadays because of their high sensibility (Karthega, 2008;Oliveira Brett, 2003). The corrosion resistance parameters were comparatively studied by potentiodynamic polarization and electrochemical impedance spectroscopies (EIS).…”

Disposable Electrochemical Biosensor with Multiwalled Carbon Nanotubes-Chitosan Composite Layer for the Detection of Deep DNA Damage

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Electrochemical oxidation of inosine-5′-triphosphate at pyrolytic graphite electrode

“…However, it is well documented in the literature that the initial oxidation of nucleosides and nucleotides occurs in the heterocyclic ring (base) [28]. Hence, initial 2e − , 2H + oxidation of 5 -ITP in the primary electrode reaction follows the same route as described for hypoxanthine [29,30] leading to the formation of 8-hydroxyinosine-5 -triphosphate (2).…”