Carbon nanotubes and (4-((E)-(2-methyl-4-nitrophenylimino) methyl) benzene-1,2-diol) modified glassy carbon electrode as a new electrocatalyst for oxidation of levodopa

Abstract

This work investigates the electrocatalytic activity of (4-((E)-(2-methyl-4-nitrophenylimino) methyl) benzene-1,2-diol) and multi-wall carbon nanotubes (MNB-MWCNT-GCE) for levodopa (LD) oxidation. At first the electrochemical behavior of MNB as a newly synthesized compound was studied; the apparent electron transfer rate constant of k_s = 36.3 s⁻¹ and electron transfer coefficient of α = 0.47 was obtained for MNB. The modified electrode showed an electrocatalytic activity for oxidation of LD with the catalytic reaction rate constant of k_h = 324.75 M⁻¹ s⁻¹. The peak potential for the oxidation of LD at the modified electrode was lowered by at least 326 mV from the unmodified electrode. Additionally, the proposed electrocatalyst was used as a LD sensor. This sensor showed a linear response in the range of 5.0 × 10⁻⁷ − 9.0 × 10⁻⁴ M and a detection limit of 3.7 × 10⁻⁷ M for LD.