Compression and stretching of a self-avoiding chain in cylindrical nanopores

Abstract

Force-induced deformations of a self-avoiding chain confined inside a cylindrical cavity, with diameter $D$, are probed using molecular dynamics simulations, scaling analysis, and analytical calculations. We obtain and confirm a simple scaling relation $-f\cdot D\sim R^{-9/4}$ in the strong-compression regime, while for weak deformations we find $f\cdot D=-A(R/R_0)+B(R/R_0{)}^{-2}$, where $A$ and $B$ are constants, $f$ the external force, and $R$ the chain extension (with $R_0$ its unperturbed value). For a strong stretch, we present a universal, analytical force-extension relation. Our results can be used to analyze the behavior of biomolecules in confinement.

4 + epsilon pages, 3 figures. To appear in Physical Review Letters

References in corpus (2)

• Unexpected relaxation dynamics of a self-avoiding polymer in cylindrical confinement
• Stretching Homopolymers