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Reversible control of current across lipid membranes by local heating.

ABSTRACT: Lipid membranes are almost impermeable for charged molecules and ions that can pass the membrane barrier only with the help of specialized transport proteins. Here, we report how temperature manipulation at the nanoscale can be employed to reversibly control the electrical resistance and the amount of current that flows through a bilayer membrane with pA resolution. For this experiment, heating is achieved by irradiating gold nanoparticles that are attached to the bilayer membrane with laser light at their plasmon resonance frequency. We found that controlling the temperature on the nanoscale renders it possible to reproducibly regulate the current across a phospholipid membrane and the membrane of living cells in absence of any ion channels.

SUBMITTER: Urban P

PROVIDER: S-EPMC4778043 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Reversible control of current across lipid membranes by local heating.

Urban Patrick P Kirchner Silke R SR Mühlbauer Christian C Lohmüller Theobald T Feldmann Jochen J

Scientific reports 20160304

Lipid membranes are almost impermeable for charged molecules and ions that can pass the membrane barrier only with the help of specialized transport proteins. Here, we report how temperature manipulation at the nanoscale can be employed to reversibly control the electrical resistance and the amount of current that flows through a bilayer membrane with pA resolution. For this experiment, heating is achieved by irradiating gold nanoparticles that are attached to the bilayer membrane with laser lig ...[more]

PMID: 26940847

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