Highly stretched single polymers: atomic-force-microscope experiments versus ab-initio theory.

Thorsten Hugel; Matthias Rief; Markus Seitz; Hermann E Gaub; Roland R Netz

doi:10.1103/physrevlett.94.048301

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Highly stretched single polymers: atomic-force-microscope experiments versus ab-initio theory.

Thorsten Hugel·Matthias Rief·Markus Seitz·Hermann E Gaub·Roland R Netz

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Abstract

Experimental single-molecule stretching curves for three backbone architectures (single-stranded DNA, various types of peptides, polyvinylamine) are quantitatively compared with corresponding quantum-chemical (zero-temperature) ab-initio calculations in the high-force range of up to two nanonewtons. For high forces, quantitative agreement is obtained with the contour length of the polymers as the only fitting parameter. For smaller forces, the effects of chain fluctuations are accounted for by using recent theoretical results for the stretching response of a freely-rotating-chain model.

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Computer Simulation DNA Elasticity Microscopy, Atomic Force Models, Chemical Models, Molecular Molecular Conformation Peptides Polymers Polyvinyls Stress, Mechanical Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Thorsten Hugel, Matthias Rief, Markus Seitz, Hermann E Gaub, Roland R Netz. 2005-01-31. Highly stretched single polymers: atomic-force-microscope experiments versus ab-initio theory.. https://doi.org/10.1103/physrevlett.94.048301

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