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dsDNA persistence length with divalent ions

Soft Condensed Matter 2023-06-27 v1 Biological Physics

Abstract

Finding a theoretical formula for the persistence length of polyelectrolytes for the whole experimental range of salt concentration is a long standing challenge. Using the Tethered Particle Motion technique, the double-stranded DNA persistence length is measured for four monovalent and divalent salts on a three-decade concentration range. The formula proposed by Trizac and Shen [EPL, 116 18007 (2016)] and extended to divalent ions fits the data. This formula mixes the high salt limit solution of the Poisson-Boltzmann equation together with the DNA charge renormalisation. Magnesium ions induce a fitted DNA radius smaller than the geometrical one, consistent with a site-specific binding.

Keywords

Cite

@article{arxiv.2306.14758,
  title  = {dsDNA persistence length with divalent ions},
  author = {Manoel Manghi and Audrey Denis and Nicolas Destainville and Emmanuel Trizac and Catherine Tardin},
  journal= {arXiv preprint arXiv:2306.14758},
  year   = {2023}
}
R2 v1 2026-06-28T11:14:38.957Z