Electrochemical Characteristics of Vitamin K3 Incorporated in Carbon Nanotubes–Chitosan Hybrid Films and the Electrocatalytic Oxidation of Dopamine

Abstract

The electrochemical characteristics of vitamin (denoted ) incorporated in acid-treated multiwalled carbon nanotubes (MWNTs)–chitosan (CHIT) hybrid films in phosphate buffer solutions were determined and the electrocatalytic oxidation of dopamine (DA) was investigated. It was shown that the adsorbility of on the surface of a glassy carbon electrode was greatly enhanced by CHIT and MWNTs. Cyclic voltammetric measurements revealed that the redox peak currents of increased dramatically with the addition of MWNTs. The apparent charge-transfer rate constant and transfer coefficient α for electron transfer between the electrode surface and immobilized in MWNTs–CHIT hybrid films and in MWNT films were calculated as , 0.49 and , 0.47, respectively. The electrocatalytic oxidation of DA evaluated by cyclic voltammetric measurements indicates that –MWNTs–CHIT hybrid film modified electrodes have good electrocatalytic property to DA. The differential pulse voltammograms were used to detect the DA concentration. A linear relationship between steady-state current and DA concentration was obtained over the range of with a detection limit of .