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arXiv · 1508.04528

Differential stability of DNA based on salt concentration

Arghya Maity·Amar Singh·Navin Singh
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Abstract

Intracellular positive ions neutralise negative charges on the phosphates of a DNA strand conferring greater strength on the hydrogen bonds that connect complementary strands into a double helix and so confer enhanced stability. Beyond a certain value of salt concentration, the DNA molecule displays a unstable nature {\it in vivo} as well as {\it in vitro}. We consider a wide range of salt concentrations and study the stability of the DNA double helix using a statistical model. Through numerical calculations we attempt to explain the different behaviour exhibited by DNA molecules in this range. We compare our results with experimental data and find a close agreement.

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Arghya Maity, Amar Singh, Navin Singh. 2015-08-19. Differential stability of DNA based on salt concentration. https://arxiv.org/abs/1508.04528

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