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Updated: Jun 25, 2026
06:45
Force Spectroscopy of Single Protein Molecules Using an Atomic Force Microscope
Published on: February 28, 2019
Exploring hysteresis and energy dissipation in single-molecule force spectroscopy.
Zion Tshiprut1, Michael Urbakh
1School of Chemistry, Tel Aviv University, 69978 Tel Aviv, Israel.
The Journal of Chemical Physics
|March 5, 2009
Summary
This study introduces an analytical method to understand active rebinding and force hysteresis in single-molecule pulling experiments. Analyzing unbinding and rebinding forces enhances the accuracy of molecular complex parameter retrieval.
Area of Science:
- Biophysics
- Single-molecule biophysics
- Molecular dynamics
Background:
- Single-molecule pulling experiments reveal complex behaviors like force hysteresis.
- Understanding active rebinding is crucial for characterizing molecular interactions.
Purpose of the Study:
- To develop an analytical approach for describing active rebinding and force hysteresis.
- To derive equations relating measured quantities to molecular potential properties, spring stiffness, and pulling velocity.
Main Methods:
- Derivation of analytical equations.
- Comparison of analytical results with Langevin simulations.
Main Results:
- Energy dissipation per cycle increases with molecular potential steepness and decreases with spring stiffness.
- Scaling relations for barrier heights and forces are more accurate for active rebinding than unbinding.
- Simultaneous analysis of unbinding and rebinding force probability densities improves parameter retrieval accuracy.
Conclusions:
- The proposed analytical approach accurately describes active rebinding and force hysteresis.
- Simultaneous analysis of force probability densities offers a more precise method for determining molecular complex parameters.
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