skip to main content

Title: Force-extension curves for broken-rod macromolecules: Dramatic effects of different probing methods for two and three rods

We study force-extension curves of a single semiflexible chain consisting of several rigid rods connected by flexible spacers. The atomic force microscopy and laser optical or magnetic tweezers apparatus stretching these rod-coil macromolecules are discussed. In addition, the stretching by external isotropic force is analyzed. The main attention is focused on computer simulation and analytical results. We demonstrate that the force-extension curves for rod-coil chains composed of two or three rods of equal length differ not only quantitatively but also qualitatively in different probe methods. These curves have an anomalous shape for a chain of two rods. End-to-end distributions of rod-coil chains are calculated by Monte Carlo method and compared with analytical equations. The influence of the spacer’s length on the force-extension curves in different probe methods is analyzed. The results can be useful for interpreting experiments on the stretching of rod-coil block-copolymers.
Authors:
; ;  [1] ;  [2] ;  [3]
  1. Faculty of Physics, Moscow State University, 119991 Moscow (Russian Federation)
  2. Department of Physics, American University of Beirut, P.O. Box 11-0236, Beirut 1107 2020 (Lebanon)
  3. Chemical-Pharmaceutical Academy, Prof. Popova 14, 197022 St. Petersburg (Russian Federation)
Publication Date:
OSTI Identifier:
22415725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 16; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; COPOLYMERS; DIAGRAMS; LASER RADIATION; MICROSCOPY; MOLECULES; MONTE CARLO METHOD; PROBES; RODS; SPACERS