Ideal-Chain Collapse in Biopolymers

Richard M. Neumann

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arXiv · physics/0011067

Ideal-Chain Collapse in Biopolymers

Richard M. Neumann

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Abstract

A conceptual difficulty in the Hooke's-law description of ideal Gaussian polymer-chain elasticity is sometimes apparent in analyses of experimental data or in physical models designed to simulate the behavior of biopolymers. The problem, the tendency of a chain to collapse in the absence of external forces, is examined in the following examples: DNA-stretching experiments, gel electrophoresis, and protein folding. We demonstrate that the application of a statistical-mechanically derived repulsive force, acting between the chain ends, whose magnitude is proportional to the absolute temperature and inversely proportional to the scalar end separation removes this difficulty.

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Richard M. Neumann. 2000-12-18. Ideal-Chain Collapse in Biopolymers. https://arxiv.org/abs/physics/0011067

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