Interactions between avidin and graphene for development of a biosensing platform

Area of Science:

• Biomaterials Science
• Nanotechnology
• Biophysics

Background:

• Understanding protein-nanomaterial interactions is vital for biocompatible hybrid materials and biosensing.
• Graphene-based nanomaterials offer enhanced sensitivity and reliability in biosensors due to their large surface area and conductivity.
• Conductive nanocomposites immobilizing proteins improve biosensor performance by combining transducer and recognition element properties.

Purpose of the Study:

• To investigate the interactions between avidin and graphene for a novel biosensing platform.
• To develop a platform for detecting biological macromolecules, such as mismatch repair proteins, using biotinylated DNA substrates.

Main Methods:

• Combined molecular dynamics (MD) simulations and experimental approaches.
• Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) for structural analysis.
• Electrochemical impedance spectroscopy (EIS) to analyze avidin immobilization on graphenated polypyrrole (G-PPy).

Main Results:

• Avidin and graphene interactions are primarily hydrophobic, with contributions from van der Waals, electrostatic, and hydrogen bonding forces.
• Avidin's structure and function are largely maintained after adsorption onto the graphene surface.
• Experimental results (SEM, FTIR, EIS) corroborate MD findings on avidin adsorption onto graphene nanoplatelets.

Conclusions:

• The study provides fundamental insights into avidin-graphene interactions, crucial for biosensor development.
• The developed sensing platform demonstrates potential for detecting specific biological macromolecules.
• The preservation of avidin's integrity on graphene suggests its suitability for various biosensing applications.