Accessibility of Densely Localized DNA on Soft Polymer Nanoparticles

Area of Science:

• Biomaterials Science
• Nanotechnology
• Molecular Biology

Background:

• Dense DNA packing on nanoparticles can alter DNA behavior compared to solution.
• The structure of nanoparticle assembly influences DNA accessibility and function.
• Bottle-brush polymers offer a unique scaffold for dense DNA presentation.

Purpose of the Study:

• To investigate the accessibility of DNA duplexes densely packed on a bottle-brush polymer core.
• To compare DNA accessibility on bottle-brush polymers with spherical nucleic acids.
• To determine if DNA on bottle-brush polymers can undergo enzymatic degradation and strand exchange.

Main Methods:

• Synthesized bottle-brush polymers with extending DNA duplexes.
• Assessed DNA accessibility using sequence-specific endonuclease cleavage.
• Evaluated DNA strand displacement via toehold-mediated strand exchange.

Main Results:

• DNA duplexes on bottle-brush polymers were accessible to sequence-specific endonuclease cleavage.
• Unlike spherical nucleic acids, bottle-brush polymer-bound DNA remained cleavable.
• Toehold-mediated strand exchange successfully displaced hybridized DNA strands at the polymer interface.
• Demonstrated the flexibility of DNA on bottle-brush polymers.

Conclusions:

• DNA densely packed on bottle-brush polymers retains flexibility.
• This flexibility allows for enzymatic degradation and DNA hybridization.
• Bottle-brush polymer-DNA nanostructures offer distinct functional properties compared to spherical nucleic acids.