Electrochemistry of Hemin Self‐Assembled from Aqueous Hexadecyltrimethylammonium Bromide (CTAB) Solution on Single‐Wall‐Carbon‐Nanotube‐Modified Glassy Carbon Electrodes

Abstract

Abstractmagnified imageHemin could be dissolved directly in H2O solution in the presence of the cationic surfactant hexadecyltrimethylammonium bromide (CTAB). The hemin is adsorbed on the surface of single‐wall‐carbon‐nanotube‐modified glassy carbon (GC) electrodes by self‐assembly. The modified electrodes exhibit a well‐defined, reversible redox peak with the reduction potential at −0.30 V and a potential separation of 61 mV at pH 7.0. The peak current is found to increase linearly with the scan rate in the range 25–200 mV, and the peak potential is pH‐dependent. The modified electrodes exhibit obvious signal enhancement for the electrochemical reduction of O2 and H2O2, and oxidation of L‐cysteine, which is useful to develop their application in electroanalysis and biosensors.