How adsorption influences DNA denaturation

TL;DR

This paper investigates how attractive solid surfaces influence DNA denaturation, showing that surface adsorption can suppress phase transitions and that combined weak attractions can induce naturation and adsorption.

Contribution

It introduces a model of DNA strands as coupled flexible chains and reveals how surface interactions alter denaturation behavior and enable naturation and adsorption under combined weak attractions.

Findings

Adsorption suppresses the DNA denaturation phase transition.

Combined surface and inter-strand attractions can induce naturation and adsorption.

Weak individual attractions can jointly produce significant effects.

Abstract

The thermally induced denaturation of DNA in the presence of attractive solid surface is studied. The two strands of DNA are modeled via two coupled flexible chains without volume interactions. If the two strands are adsorbed on the surface, the denaturation phase-transition disappears. Instead, there is a smooth crossover to a weakly naturated state. Our second conclusion is that even when the inter-strand attraction alone is too weak for creating a naturated state at the given temperature, and also the surface-strand attraction alone is too weak for creating an adsorbed state, the combined effect of the two attractions can lead to a naturated and adsorbed state.