Publication detail

Electric Field Effect on Phospholipid Monolayers at an Aqueous−Organic Liquid−Liquid Interface

Hao Yu, Irena Yzeiri, Binyang Hou, Chiu-Hao Chen, Wei Bu, Petr Vanysek, Yu-Sheng Chen, Binhua Lin, Petr Král, Mark L. Schlossman

Original Title

Electric Field Effect on Phospholipid Monolayers at an Aqueous−Organic Liquid−Liquid Interface

Type

journal article in Web of Science

Language

English

Original Abstract

The electric potential difference across cell membranes, known as the membrane potential, plays an important role in the activation of many biological processes. To investigate the effect of the membrane potential on the molecular ordering of lipids within a biomimetic membrane, a self-assembled monolayer of 1-stearoyl-2-oleoyl-snglycero- 3-phosphocholine (SOPC) lipids at an electrified 1,2-dichloroethane/water interface is studied with X-ray reflectivity and interfacial tension. Measurements over a range of electric potential differences, −150 to +130 mV, that encompass the range of typical biomembrane potentials demonstrate a nearly constant and stable structure whose lipid interfacial density is comparable to that found in other biomimetic membrane systems. Measurements at higher positive potentials, up to 330 mV, illustrate a monotonic decrease in the lipid interfacial density and accompanying variations in the interfacial configuration of the lipid. Molecular dynamics simulations, designed to mimic the experimental conditions, show that the measured changes in lipid configuration are due primarily to the variation in area per lipid with increasing applied electric field. Rotation of the SOPC dipole moment by the torque from the applied electric field appears to be negligible, except at the highest measured potentials. The simulations confirm in atomistic detail the measured potentialdependent characteristics of SOPC monolayers. Our hybrid study sheds light on phospholipid monolayer stability under different membrane potentials, which is important for understanding membrane processes. This study also illustrates the use of X-ray surface scattering to probe the ordering of surfactant monolayers at an electrified aqueous−organic liquid−liquid interface.

Keywords

liquid-liquid electrochemistry; monolayer; phospholipid;

Authors

Hao Yu, Irena Yzeiri, Binyang Hou, Chiu-Hao Chen, Wei Bu, Petr Vanysek, Yu-Sheng Chen, Binhua Lin, Petr Král, Mark L. Schlossman

RIV year

2014

Released

19. 11. 2014

Publisher

American Chemical Society

ISBN

1089-5647

Periodical

JOURNAL OF PHYSICAL CHEMISTRY B

Year of study

119

Number

29

State

United States of America

Pages from

9319

Pages to

9334

Pages count

15

URL

http://pubs.acs.org/doi/abs/10.1021/jp5098525

BibTex

@article{BUT112072,
  author="Petr {Vanýsek} and Mark {Schlossman}",
  title="Electric Field Effect on Phospholipid Monolayers at an Aqueous−Organic Liquid−Liquid Interface",
  journal="JOURNAL OF PHYSICAL CHEMISTRY B",
  year="2014",
  volume="119",
  number="29",
  pages="9319--9334",
  doi="10.1021/jp5098525",
  issn="1089-5647",
  url="http://pubs.acs.org/doi/abs/10.1021/jp5098525"
}