Catalase immobilized on a functionalized multi-walled carbon nanotubes–gold nanocomposite as a highly sensitive bio-sensing system for detection of hydrogen peroxide

• Published in: Electrochimica acta Vol. 89; pp. 317 - 325
• Main Authors: Hong, Jun, Yang, Wei-Yun, Zhao, Ying-Xue, Xiao, Bao-Lin, Gao, Yun-Fei, Yang, Tian, Ghourchian, Hedayatollah, Moosavi-Movahedi, Zainab, Sheibani, Nader, Li, Jian-Guo, Moosavi-Movahedi, Ali Akbar
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2013
• Subjects: Biosensor; Catalase; Direct electrochemistry; Gold nanoparticles; Multi-walled carbon nanotubes; Catalase; Direct electrochemistry; Multi-walled carbon nanotubes; Gold nanoparticles; Biosensor
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2012.11.054

By immobilizing catalase on a nanocomposite containing functionalized multi-walled carbon nanotubes and l-cysteine modified gold nanoparticles, a third generation biosensor was developed for determination of the hydrogen peroxide. The cyclic voltammograms of catalase on the nanocomposite modified glassy carbon electrode showed a pair of well-defined quasi-reversible redox peaks with the formal potential of −441±2mV versus Ag/AgCl at a scan rate of 0.05V/s. The heterogeneous electron transfer constant was calculated to be 8.72s−1. The enzyme electrode response toward hydrogen peroxide was linear in the concentrations ranging from 1nM to 1μM, with a detection limit of 0.5nM. The apparent Michaelis–Menten constant was calculated to be 0.34μM.