Potential-Dependent Adhesion Forces between dsDNA and Electroactive Surfaces

Area of Science:

• Materials Science
• Surface Chemistry
• Biophysics

Background:

• Controlling polyelectrolyte interactions with surfaces is crucial for various applications.
• Existing electroactive groups often lack the stability required for practical use.

Purpose of the Study:

• To investigate the use of a stable electroactive surface for tunable polyelectrolyte interactions.
• To quantify the relationship between surface charge state and DNA adhesion forces.

Main Methods:

• Single-molecule force spectroscopy was employed to study dsDNA interactions.
• An 1,1 -biferrocenylene-terminated self-assembled monolayer (SAM) was used as the electroactive surface.
• Electrochemical potentials were used to control the oxidation state of the surface.

Main Results:

• DNA interaction forces strongly correlated with the oxidation state of the 1,1 -biferrocenylene groups.
• The electroactive SAM exhibited significantly stronger interaction forces compared to a non-electroactive surface.
• A Grahame equation-based model accurately predicted the observed potential-adhesion force relationship.

Conclusions:

• The developed electroactive surface provides a stable and tunable platform for studying polyelectrolyte-surface interactions.
• This system serves as a model for understanding and manipulating polyelectrolyte behavior.
• Potential applications include advanced biosensing, nanomotors, and controlled polyelectrolyte conformation.