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Optical stretching as a tool to investigate the mechanical properties of lipid bilayers.

ABSTRACT: Measurements of lipid bilayer bending modulus by various techniques produce widely divergent results. We attempt to resolve some of this ambiguity by measuring bending modulus in a system that can rapidly process large numbers of samples, yielding population statistics. This system is based on optical stretching of giant unilamellar vesicles (GUVs) in a microfluidic dual-beam optical trap (DBOT). The microfluidic DBOT system is used here to measure three populations of GUVs with distinct lipid compositions. We find that gel-phase membranes are significantly stiffer than liquid-phase membranes, consistent with previous reports. We also find that the addition of cholesterol does not alter the bending modulus of membranes composed of a monounsaturated phospholipid.

SUBMITTER: Solmaz ME

PROVIDER: S-EPMC3827026 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Optical stretching as a tool to investigate the mechanical properties of lipid bilayers.

Solmaz Mehmet E ME Sankhagowit Shalene S Biswas Roshni R Mejia Camilo A CA Povinelli Michelle L ML Malmstadt Noah N

RSC advances 20131001 37

Measurements of lipid bilayer bending modulus by various techniques produce widely divergent results. We attempt to resolve some of this ambiguity by measuring bending modulus in a system that can rapidly process large numbers of samples, yielding population statistics. This system is based on optical stretching of giant unilamellar vesicles (GUVs) in a microfluidic dual-beam optical trap (DBOT). The microfluidic DBOT system is used here to measure three populations of GUVs with distinct lipid c ...[more]

PMID: 24244843

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