Graphene electrochemistry: fabricating amperometric biosensors

Area of Science:

• Electrochemistry
• Materials Science
• Biosensor Technology

Background:

• Electrochemical sensing of hydrogen peroxide is crucial for oxidase-based amperometric biosensors.
• Graphene and graphite are common electrode materials with distinct electrochemical properties.

Purpose of the Study:

• To fabricate and evaluate a novel, highly sensitive electro-analytical biosensor using graphene.
• To compare the performance of Nafion-modified graphene and graphite electrodes for hydrogen peroxide detection.

Main Methods:

• Fabrication of modified electrodes using commercially available graphene and graphite.
• Electrochemical characterization and comparison of sensor responses.
• Investigation of Nafion's influence on electrode performance.

Main Results:

• Graphite electrodes exhibited a superior electrochemical response compared to graphene.
• The enhanced response of graphite is attributed to a higher percentage of edge plane sites.
• Nafion modification led to beneficial re-orientation on graphene but detrimental effects on graphite.

Conclusions:

• Graphite's edge plane sites enhance electrochemical sensing of hydrogen peroxide.
• Nafion's impact on sensor performance is material-dependent, offering insights for biosensor design.
• Graphene-based biosensors can be optimized by understanding Nafion's interaction for improved sensitivity.