Worm-Like-Chain Model of Forced Desorption of a Polymer Adsorbed on an Attractive Wall

TL;DR

This paper presents a theoretical study of forced desorption of semiflexible polymers from an attractive wall, revealing characteristic force spikes influenced by persistence length, with implications for DNA single-molecule experiments.

Contribution

It introduces a worm-like-chain model to analyze how persistence length affects force-displacement behavior during polymer desorption from an attractive surface.

Findings

Force-displacement curves show characteristic spikes.

Force spikes become more pronounced with increasing persistence length.

Average force magnitude decreases as persistence length grows.

Abstract

Forced desorption of a semiflexible polymer chain on a solid substrate is theoretically investigated. The pulling force versus displacement is studied for different adsorption energy and persistence length P. It is found that the relationships between pulling force and cantilever displacement show a series of characteristic force spikes at different persistence length P. These force spikes becomes more pronounced but the average magnitude of this force decrease as P grows. Our results are of relevance to forced desorption of DNA on an attractive wall in single-molecule pulling experiments.