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Adhesion Induced DNA Naturation

A. E. Allahverdyan·Zh. S. Gevorkian·Chin-Kun Hu·Th. M. Nieuwenhuizen
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Abstract

DNA adsorption and naturation is modeled via two interacting flexible homopolymers coupled to a solid surface. DNA denatures if the entropy gain for unbinding the two strands overcomes the loss of binding energy. When adsorbed to a surface, the entropy gain is smaller than in the bulk, leading to a stronger binding and, upon neglecting self-avoidance, absence of a denatured phase. Now consider conditions where the binding potentials are too weak for naturation, and the surface potential too weak to adsorb single strands. In a variational approach it is shown that their combined action may lead to a naturated adsorbed phase. Conditions for the absence of naturation and adsorption are derived too. The phase diagram is constructed qualitatively.

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A. E. Allahverdyan, Zh. S. Gevorkian, Chin-Kun Hu, Th. M. Nieuwenhuizen. 2005-12-12. Adhesion Induced DNA Naturation. https://doi.org/10.1103/physrevlett.96.098302

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