Direct Electrochemistry of Hemoglobin in Cerium Dioxide/Carbon Nanotubes/Chitosan for Amperometric Detection of Hydrogen Peroxide

摘要

A novel hemoglobin (Hb) biosensor based on the remarkable synergistic effects of cerium dioxide (CeO2) and multiwalled carbon nanotubes (MWNTs) for detection of hydrogen peroxide (H2O2) is presented. The Hb/CeO2/MWNTs/CHIT nanocomposite was nanoengineered by selected matched material components and optimized composition ratio to produce a superior H2O2 sensor. The preparation method is quite simple and practical. This composite matrix combined the advantages of MWNTs, CeO2 nanoparticles, and chitosan (CHIT), with good electron-transfer ability, attractive biocompatibility, and fine film-forming ability, which could increase Hb attachment quantity and H2O2 detection sensitivity. In the optimum pH 7.0 phosphate buffer, the electrocatalytic response exhibited a linear dependence on H2O2 concentration in a wide range from 5.010-6 to 4.610-4 mol L-1 with a detection limit of 6.510-7 mol/L (3).