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Hydrodynamic trapping of molecules in lipid bilayers.

ABSTRACT: In this work we show how hydrodynamic forces can be used to locally trap molecules in a supported lipid bilayer (SLB). The method uses the hydrodynamic drag forces arising from a flow through a conical pipette with a tip radius of 1-1.5 ?m, placed approximately 1 ?m above the investigated SLB. This results in a localized forcefield that acts on molecules protruding from the SLB, yielding a hydrodynamic trap with a size approximately given by the size of the pipette tip. We demonstrate this concept by trapping the protein streptavidin, bound to biotin receptors in the SLB. It is also shown how static and kinetic information about the intermolecular interactions in the lipid bilayer can be obtained by relating how the magnitude of the hydrodynamic forces affects the accumulation of protein molecules in the trap.

SUBMITTER: Jonsson P

PROVIDER: S-EPMC3387037 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Hydrodynamic trapping of molecules in lipid bilayers.

Jönsson Peter P McColl James J Clarke Richard W RW Ostanin Victor P VP Jönsson Bengt B Klenerman David D

Proceedings of the National Academy of Sciences of the United States of America 20120614 26

In this work we show how hydrodynamic forces can be used to locally trap molecules in a supported lipid bilayer (SLB). The method uses the hydrodynamic drag forces arising from a flow through a conical pipette with a tip radius of 1-1.5 μm, placed approximately 1 μm above the investigated SLB. This results in a localized forcefield that acts on molecules protruding from the SLB, yielding a hydrodynamic trap with a size approximately given by the size of the pipette tip. We demonstrate this conce ...[more]

PMID: 22699491

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