Novel Hydrogen Peroxide Sensor using a Multiwalled Carbon Nanotube-Cobalamin Nanocomposite Glassy Carbon Electrode

Abstract

A novel nonenzymatic sensor for the determination of hydrogen peroxide was developed based on a multiwalled carbon nanotube-cobalamin composite using simple electrodeposition. The presence of multiwalled carbon nanotubes in the composite film of the modified glassy carbon electrode mediated the cobalamin redox reaction. The composite modified electrode exhibited good electrocatalytic activity for the determination of hydrogen peroxide by cyclic voltammetry. Linear response of the sensor was obtained for analyte concentrations from 24–3120 μM. The sensitivity was approximately 56.5 μA cm⁻² μM⁻¹ and the limit of detection was 0.56 μM. The multiwalled carbon nanotube-cobalamin modified sensor provided suitable long-term stability with relatively rapid and reproducible response towards hydrogen peroxide, providing a promising platform for real sample analysis.

Keywords:

• cobalamin
• cyclic voltammetry
• electrocatalysis
• hydrogen peroxide
• modified electrode
• multiwalled carbon nanotube
• reduced graphene oxide