Published July 2015 | Version v1
Miscellaneous

The effect of bias potential on thehered lipid bialayers

  • 1. Australian Nuclear Science and Technology Organisation, Lucas Heights (Australia)
  • 2. University of Technology, Sydney, Sydney (Australia)
  • 3. Sugrical Diagnostics, Roseville (Australia)

Description

Tethered lipid bilayer membranes (tBLMs) are membranes chemically anchored to solid substrates typically employing sulphur-gold chemistry. Such membranes represent stable, convenient models of complex biological membranes and are particularly suited to physical techniques such as Neutron Scatteringand electrical impedance spectroscopy (EIS). We have devised a tBLM architecture comprising a benzyl disulphide – O11 ethylene glycol – C20 phytanyl tether which when mixed in various ratios with a benzyl disulphide O4 – OH spacers provides a sparsely tethered tBLM possessing a hydrophilic volume between a subsequently formed lipid bilayer membrane and the tethering gold electrode surface. A critical feature of this architecture is the spacing of this layer, and the volume of water stored therein. A bias potential may be applied very simply through the application of voltage gradients between the conductive supportive gold surface and a return electrode within the bathing solution. This permits control over the potential gradients across membranes and the determination of the transport properties of membrane incorporated biological ion channels and carriers. For example the ion channel conductance (gramicidin-A in this case) may be altered by an order of magnitude in tBLMS by the application of bias voltage. This suggests the selective sequestration of ions into the reservoir space. We have commenced simultaneous Neutron Reflection and EIS studies of the impact of bias voltage upon the properties of tBLMs where we have varied the density of the tethering layer and examined the impact of 0 & ± 300 mV upon the position of the bilayer relative to the tethering substrate. The figure shows data (March 2015) for a fully tethered bilayer. There is a small, but clear impact of bias potential on the dataset, which correlates with the EIS data. The data was collected at 0, then + 300 mV followed by a return to – 300 mV. Analysis of data and from this and other tethering density tBLMs has commenced and will be presented.

Additional details

Publishing Information

Imprint Title
2nd Asia Oceania Conference on Neutron Scattering(AOCNS) 2015
Imprint Pagination
276 p.
Journal Page Range
p. 7

Conference

Title
2. Asia Oceania Conference on Neutron Scattering
Acronym
AOCNS 2015
Dates
19-23 Jul 2015
Place
Sydney, NSW (Australia)

INIS

Country of Publication
Australia
Country of Input or Organization
Australia
INIS RN
46123344
Subject category
S74: ATOMIC AND MOLECULAR PHYSICS; S73: NUCLEAR PHYSICS AND RADIATION PHYSICS;
Resource subtype / Literary indicator
Conference, Non-conventional Literature
Quality check status
Yes
Descriptors DEI
BENZYL ALCOHOL; IONS; LIPIDS; MEMBRANES; NEUTRON REFLECTORS; SCATTERING; SPECTROSCOPY;
Descriptors DEC
ALCOHOLS; AROMATICS; CHARGED PARTICLES; HYDROXY COMPOUNDS; ORGANIC COMPOUNDS;

Optional Information

Lead record
qj7r9-sth43