The graphene oxide-multiwall carbon nanotubes (GO-MWNTs) were synthesized via a simple self-assembly strategy. As shown in the figure, the pristine MWNTs are assembled onto a graphene oxide nanosheet to form an integrated nanocomposite via the π–π interaction.

The adsorption of the GO nanosheet onto pristine MWNTs not only stabilized the hydrophobic nanotubes, allowing them to disperse well in aqueous solution, but also endowed the MWNTs with a negative charge – further immobilizing the positive charge of redox horseradish peroxidase (HRP) via electrostatic assembly under mild conditions.

Because of the large surface area and conductivity of the nanocomposite, the direct electron transfer between the immobilized HRP and glassy carbon (GC) electrode can be successfully achieved at the HRP/GO-MWNTs/GC electrode. What's more, the biosensor also exhibits an excellent analytical performance towards the reduction of hydrogen peroxide.

The team's results provide a new, simple and efficient method for the fabrication of electrochemical biosensors. In addition, the applications of such a novel nanocomposite in the field of biomedical devices and bioelectronics can also be envisioned.

More information can be found in the journal Nanotechnology.