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Title: Hydration effect on the structure of dioleoylphosphatidylcholine bilayers

Abstract

In situ enersgy dispersive x-ray diffraction was used to study the effect of hydration on the structure of dioleoylphosphatidylcholine (DOPC) bilayers in the biologically relevant liquid-crystalline phase. A broad range of relative humidity (RH) was investigated (0.45<RH<1) and two hydration regimes were found. From RH=0.45 up to RH{approx}0.94, the structure of DOPC bilayers was found to change slightly. At RH{approx}0.94, a distinctive structural change was observed. From RH{approx}0.94 up to full hydration, a strong increase in the head group size, coupled with a marked decrease in the hydrophobic core thickness, was observed. Possible molecular mechanisms underlying experimental observations are discussed.

Authors:
; ;  [1]
  1. Department of Chemistry, University of Rome 'La Sapienza', P.le A. Moro 5, 00185 Rome (Italy)
Publication Date:
OSTI Identifier:
20971912
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 18; Other Information: DOI: 10.1063/1.2734470; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BIOCHEMISTRY; BIOPHYSICS; CHEMICAL ANALYSIS; HUMIDITY; HYDRATION; LAYERS; LIPIDS; LIQUID CRYSTALS; X-RAY DIFFRACTION

Citation Formats

Caracciolo, Giulio, Pozzi, Daniela, and Caminiti, Ruggero. Hydration effect on the structure of dioleoylphosphatidylcholine bilayers. United States: N. p., 2007. Web. doi:10.1063/1.2734470.
Caracciolo, Giulio, Pozzi, Daniela, & Caminiti, Ruggero. Hydration effect on the structure of dioleoylphosphatidylcholine bilayers. United States. doi:10.1063/1.2734470.
Caracciolo, Giulio, Pozzi, Daniela, and Caminiti, Ruggero. Mon . "Hydration effect on the structure of dioleoylphosphatidylcholine bilayers". United States. doi:10.1063/1.2734470.
@article{osti_20971912,
title = {Hydration effect on the structure of dioleoylphosphatidylcholine bilayers},
author = {Caracciolo, Giulio and Pozzi, Daniela and Caminiti, Ruggero},
abstractNote = {In situ enersgy dispersive x-ray diffraction was used to study the effect of hydration on the structure of dioleoylphosphatidylcholine (DOPC) bilayers in the biologically relevant liquid-crystalline phase. A broad range of relative humidity (RH) was investigated (0.45<RH<1) and two hydration regimes were found. From RH=0.45 up to RH{approx}0.94, the structure of DOPC bilayers was found to change slightly. At RH{approx}0.94, a distinctive structural change was observed. From RH{approx}0.94 up to full hydration, a strong increase in the head group size, coupled with a marked decrease in the hydrophobic core thickness, was observed. Possible molecular mechanisms underlying experimental observations are discussed.},
doi = {10.1063/1.2734470},
journal = {Applied Physics Letters},
number = 18,
volume = 90,
place = {United States},
year = {Mon Apr 30 00:00:00 EDT 2007},
month = {Mon Apr 30 00:00:00 EDT 2007}
}
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