Myoglobin within graphene oxide sheets and Nafion composite films as highly sensitive biosensor

Area of Science:

• Electrochemistry
• Materials Science
• Biotechnology

Background:

• Myoglobin (Mb) is a protein with potential biosensing applications.
• Graphene oxide (GO) and Nafion are advanced materials for biosensor fabrication.
• Direct electron transfer (DET) in biosensors enhances sensitivity and reduces complexity.

Purpose of the Study:

• To fabricate a highly sensitive biosensor using a myoglobin-graphene oxide-Nafion composite film.
• To characterize the electrochemical properties and stability of the Mb-GO-Nafion composite.
• To evaluate the electrocatalytic activity of the fabricated biosensor towards various substrates.

Main Methods:

• Fabrication of myoglobin-graphene oxide-Nafion composite films on a glassy carbon electrode.
• Electrochemical characterization using cyclic voltammetry.
• Structural and spectral analysis using scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-vis spectroscopy.

Main Results:

• The Mb-GO-Nafion films exhibited stable and well-defined quasi-reversible peaks, indicating efficient direct electron transfer (DET).
• Myoglobin retained its native secondary structure within the composite film.
• The biosensor demonstrated good electrocatalytic activity towards hydrogen peroxide, nitrite, and oxygen.

Conclusions:

• The developed Mb-GO-Nafion composite film is a promising platform for highly sensitive, mediator-free biosensors.
• The biosensor's performance is attributed to the synergistic effects of Mb, GO, and Nafion, facilitating DET.
• This approach holds potential for novel biosensor development in various applications.