Electrocatalytic Oxidation of Norepinephrine at a Glassy Carbon Electrode Modified with Single Wall Carbon Nanotubes

Abstract

The voltammetric behavior of norepinephrine (NE) was studied at a glassy carbon (GC) electrode modified with single wall carbon nanotubes (SWNTs). In pH 5.72 B-R buffer solution, the SWNT-modified electrode shows high electrocatalytic activity toward NE oxidation. One well-defined reversible redox couple is obtained at scan rates lower than 0.15 V s−1. The peak current increases linearly with the concentration of NE in the range of 1.0×10−5 - 1.1×10−3 mol dm−3. The detection limit is 6.0×10−6 mol dm−3 and the diffusion coefficient (D) of NE is 8.53×10−6 cm2 s−1. The SWNT was characterized with scanning electron microscope (SEM). Furthermore, the SWNT-modified electrode has favorable electrocatalytic activity with dopamine, epinephrine, and ascorbic acid.