Dopamine sensing with carbon nanotubes and graphite electrodes

Abstract

The superior material properties of carbon nanotubes (CNTs) such as high aspect ratio, high surface area, superb mechanical properties, thermal and chemical stability have generated enormous research activities to push for their potential applications. This study focuses on the fabrication and characterization of CNTs synthesized by hot filament chemical vapor deposition and evaluates their use as electrochemical biosensor. The as grown CNTs were first characterized for their electrochemical behavior in ferrocyanide redox reaction using cyclic voltammetric analysis. Then, their use for dopamine detection was investigated. Well-established redox reaction current peaks for dopamine/o-quinone and the secondary redox reaction current peaks for leucodopominechrome/dopaminechrome were reproducibility observed with distinct redox current peak increments as a function of the bioanalyte concentration. These results were also confirmed by Cottrell and Nernst equations. In general, the results have demonstrated that CNTs are better than graphite as biosensor electrode for the detection of dopamine.