Issue
EPL
Volume 81, Number 4, February 2008
Article Number 48001
Number of page(s) 6
Section Interdisciplinary Physics and Related Areas of Science and Technology
DOI http://dx.doi.org/10.1209/0295-5075/81/48001
Published online 16 January 2008
EPL, 81 (2008) 48001
DOI: 10.1209/0295-5075/81/48001

Dynamic force spectroscopy on multiple bonds: Experiments and model

T. Erdmann1, 2, S. Pierrat3, P. Nassoy3 and U. S. Schwarz1

1  University of Heidelberg, Bioquant 0013 - Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany
2  FOM Institute for Atomic and Molecular Physics - Kruislaan 407, 1098 SJ Amsterdam, The Netherlands
3  Laboratoire de Physico-Chimie Curie, Institut Curie - F-75005 Paris, France


received 26 January 2007; accepted in final form 12 December 2007; published February 2008
published online 16 January 2008

Abstract
We probe the dynamic strength of multiple biotin-streptavidin adhesion bonds under linear loading using the biomembrane force probe setup for dynamic force spectroscopy. Measured rupture force histograms are compared to results from a master equation model for the stochastic dynamics of bond rupture under load. This allows us to extract the distribution of the number of initially closed bonds. We also extract the molecular parameters of the adhesion bonds, in good agreement with earlier results from single-bond experiments. Our analysis shows that the peaks in the measured histograms are not simple multiples of the single-bond values, but follow from a superposition procedure which generates different peak positions.

PACS
87.15.By - Biomolecules: structure and physical properties: Structure and bonding.
82.39.-k - Chemical kinetics in biological systems.
87.64.-t - Spectroscopic and microscopic techniques in biophysics and medical physics.

© EPLA 2008