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Updated: Mar 30, 2026
10:15
Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
15.6K
Hydrodynamic Forces on Macromolecules Protruding from Lipid Bilayers Due to External Liquid Flows
Peter Jönsson1, Bengt Jönsson1
1Division of Physical Chemistry and ‡Division of Biophysical Chemistry, Lund University , SE-22100 Lund, Sweden.
Langmuir : the ACS Journal of Surfaces and Colloids
|November 3, 2015
Summary
Hydrodynamic shear flow exerts forces on membrane-associated macromolecules. These forces, quantified by simulations, depend on molecular size and shape, with experimental data validating the findings for studying membrane interactions.
Area of Science:
- Biophysics
- Fluid Dynamics
- Materials Science
Background:
- Externally applied hydrodynamic shear flow influences macromolecule concentration near lipid bilayers.
- Hydrodynamic forces drive protruding molecules in the direction of flow, but magnitudes were unquantified.
Purpose of the Study:
- To quantitatively investigate the magnitude of hydrodynamic forces on macromolecules associated with lipid bilayers.
- To determine how macromolecule size and shape influence these hydrodynamic forces.
Main Methods:
- Finite element simulations were employed to model hydrodynamic forces.
- Simulations related force to effective hydrodynamic area (Ahydro) and shear stress (σhydro).
- Experiments used streptavidin on supported lipid bilayers in microfluidic channels with varying surface concentrations.
Main Results:
- Hydrodynamic force is proportional to the effective hydrodynamic area (Ahydro) and mean shear stress (σhydro).
- Ahydro scales with molecular cross-sectional area and is reduced by hydrodynamic shielding from neighboring molecules.
- Experimental drift data for streptavidin showed less than 12% difference from simulation results.
Conclusions:
- The study provides a quantitative understanding of hydrodynamic forces acting on membrane-associated macromolecules.
- Hydrodynamic flow experiments can be utilized to study macromolecule size and intermolecular forces in membranes.
- Findings offer insights into fluid flow effects on lipid bilayer-associated molecules.
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