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Title: Formation, Stability, and Mobility of One-Dimensional Lipid Bilayer on High Curvature Substrates

Abstract

Curved lipid membranes are ubiquitous in living systems and play an important role in many biological processes. To understand how curvature and lipid composition affect membrane formation and fluidity we have assembled and studied mixed 1,2-Dioleoyl-sn-Glycero-3-Phosphocholine (DOPC) and 1,2-Dioleoyl-sn-Glycero-3-Phosphoethanolamine (DOPE) supported lipid bilayers on amorphous silicon nanowires with controlled diameters ranging from 20 nm to 200 nm. Addition of cone-shaped DOPE molecules to cylindrical DOPC molecules promotes vesicle fusion and bilayer formation on smaller diameter nanowires. Our experiments demonstrate that nanowire-supported bilayers are mobile, exhibit fast recovery after photobleaching, and have low concentration of defects. Lipid diffusion coefficients in these high-curvature tubular membranes are comparable to the values reported for flat supported bilayers and increase with decreasing nanowire diameter.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
920882
Report Number(s):
UCRL-JRNL-229513
TRN: US200805%%231
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters, vol. 7, no. 11, September 27, 2007, pp. 3355-3359; Journal Volume: 7; Journal Issue: 11
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; DEFECTS; DIFFUSION; LIPIDS; MEMBRANES; SILICON; STABILITY; SUBSTRATES

Citation Formats

Huang, J, Martinez, J, Artyukhin, A, Sirbuly, D, Wang, Y, Ju, J W, Stroeve, P, and Noy, A. Formation, Stability, and Mobility of One-Dimensional Lipid Bilayer on High Curvature Substrates. United States: N. p., 2007. Web.
Huang, J, Martinez, J, Artyukhin, A, Sirbuly, D, Wang, Y, Ju, J W, Stroeve, P, & Noy, A. Formation, Stability, and Mobility of One-Dimensional Lipid Bilayer on High Curvature Substrates. United States.
Huang, J, Martinez, J, Artyukhin, A, Sirbuly, D, Wang, Y, Ju, J W, Stroeve, P, and Noy, A. Fri . "Formation, Stability, and Mobility of One-Dimensional Lipid Bilayer on High Curvature Substrates". United States. doi:. https://www.osti.gov/servlets/purl/920882.
@article{osti_920882,
title = {Formation, Stability, and Mobility of One-Dimensional Lipid Bilayer on High Curvature Substrates},
author = {Huang, J and Martinez, J and Artyukhin, A and Sirbuly, D and Wang, Y and Ju, J W and Stroeve, P and Noy, A},
abstractNote = {Curved lipid membranes are ubiquitous in living systems and play an important role in many biological processes. To understand how curvature and lipid composition affect membrane formation and fluidity we have assembled and studied mixed 1,2-Dioleoyl-sn-Glycero-3-Phosphocholine (DOPC) and 1,2-Dioleoyl-sn-Glycero-3-Phosphoethanolamine (DOPE) supported lipid bilayers on amorphous silicon nanowires with controlled diameters ranging from 20 nm to 200 nm. Addition of cone-shaped DOPE molecules to cylindrical DOPC molecules promotes vesicle fusion and bilayer formation on smaller diameter nanowires. Our experiments demonstrate that nanowire-supported bilayers are mobile, exhibit fast recovery after photobleaching, and have low concentration of defects. Lipid diffusion coefficients in these high-curvature tubular membranes are comparable to the values reported for flat supported bilayers and increase with decreasing nanowire diameter.},
doi = {},
journal = {Nano Letters, vol. 7, no. 11, September 27, 2007, pp. 3355-3359},
number = 11,
volume = 7,
place = {United States},
year = {Fri Mar 23 00:00:00 EDT 2007},
month = {Fri Mar 23 00:00:00 EDT 2007}
}
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