Dependencies between effective parameters in coarse-grained models for phase separation of DNA-based fluids.

Area of Science:

• Biophysics
• Materials Science
• Polymer Chemistry

Background:

• DNA is a robust platform for synthetic nanostructures.
• Little is known about large-scale structure formation in DNA fluids.
• DNA fluids can phase separate, enabling hierarchical assemblies.

Purpose of the Study:

• Investigate the phase behavior of single-stranded DNA fluids.
• Model DNA fluids using semiflexible charged homopolymers, excluding hybridization.
• Assess the model's ability to capture experimental data.

Main Methods:

• Characterized single-polymer behavior.
• Performed direct coexistence simulations.
• Validated the minimal model against experimental data.

Main Results:

• A minimal model of semiflexible charged homopolymers can capture DNA fluid phase behavior.
• Low-resolution models show potential for bridging length and time scales.
• Counterions significantly impact electrostatic interactions and effective attractions.

Conclusions:

• Minimal models require careful parameterization for consistency and transferability.
• Counterions play a dual role in DNA fluid electrostatics and effective attractions.
• This research provides insights into designing large-scale DNA-based assemblies.