Electrostatics of a Tetra-Stranded Polymer: Ionic Condensation and Nonlinear Screening

This work develops a dedicated electrostatic framework for a canonical tetra-stranded hereditary polymer (Q-DNA), addressing the principal physical limitation of four-strand genome architectures: electrostatic repulsion between multiple negatively charged backbones. Extending nonlinear Poisson–Boltzmann theory and ion-correlation models to tetra-stranded geometries, the manuscript analyzes how electrostatic interactions scale beyond duplex DNA and identifies regimes where mean-field screening breaks down.

The study highlights the central role of multivalent cations, polyamines, solvent dielectric properties, and molecular crowding in stabilizing tetra-stranded assemblies through counterion condensation, correlation-induced attraction, and effective ion bridging. It predicts distinct ionic fingerprints for tetra-stranded states and defines electrostatic stability windows in which four-strand architectures become energetically favorable relative to duplex DNA.

By formalizing electrostatics as a gating constraint on tetra-stranded heredity, this contribution provides quantitative and testable criteria for evaluating Q-DNA feasibility in synthetic genetics, controlled in-vitro systems, and alternative biochemical environments relevant to origins-of-life and astrobiology research.

Resource type: theoretical manuscript / electrostatic model

Intended audience: molecular biophysics, theoretical biology, synthetic genetics, and polyelectrolyte physics communities