Nanoparticles of Noble Metals as Effective Platforms for the Fabrication of Amperometric Biosensors on Hydrogen Peroxide

摘要

Hydrogen peroxide selective biosensors were developed using horseradish peroxidase (HRP) conjugated with the synthesized nanoparticles (NPs) of noble metals: AuNPs, Au/AgNPs and Ag/AuNPs. The HRP-NPs as bioelements (bioNPs) were immobilized on the surface of carbon electrodes (CE). The electrochemical performances of the resulted NPs-modified bioelectrodes (bioNPs/CEs) were studied by cyclic voltamperometry and chronoamperometry in comparison with unmodified HRP/CE-based bioelectrode (bio/CE). The HRP immobilized on the surface of NPs exhibited an excellent electrocatalytic response toward reduction of H_2O_2. All developed bioNPs/CEs showed the higher apparent Michaelis-Menten constants (K_M~(app)) values and hence expanded linear ranges toward H_2O_2 as well as higher sensitivity in comparison with bio/CE. The most effective bioAuNPs/CE biosensor was used for hydrogen peroxide analysis in the samples of industrial disinfectants. A high correlation with the hydrogen peroxide values, declared by manufacturer, was demonstrated.