Document Detail


Structure of Mixed Phosphatidylethanolamine and Cholesterol Monolayers in a Supported Hybrid Bilayer Membrane Studied by Sum Frequency Generation Vibrational Spectroscopy.
MedLine Citation:
PMID:  21542565     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
The structure of hybrid bilayer membranes (HBMs) containing either a pure cholesterol or mixed cholesterol/dipalmitoylphosphatidylethanolamine (DPPE) proximal layer adsorbed onto an octadecanethiol (ODT) self-assembled monolayer (SAM) on a gold substrate have been investigated by sum frequency generation (SFG) spectroscopy. The HBMs were formed by the adsorption of either a pure cholesterol or mixed DPPE/cholesterol monolayer from the air/water interface of a Langmuir-Blodgett trough at surface pressures of 1, 20, or 40 mN·m(-1). SFG spectra were also recorded of HBMs where cholesterol was replaced by cholesterol-d(7), in which the terminal isopropyl group of the alkyl chain of cholesterol was isotopically labeled. In order to isolate the contribution to the SFG spectra from the cholesterol in the mixed cholesterol/phospholipid films, DPPE-d was used, in which the alkyl chains of the phospholipid were deuterated. The infrared spectra of solvent-cast cholesterol and cholesterol-d(7) films were recorded to aid with assignment of the SFG spectra of the HBMs. Features corresponding to methyl, methylene, and methine stretches of cholesterol were identified in the SFG spectra. Information on the polar orientation of SFG-active groups was obtained from the phases of the spectral features. The structure of the HBMs showed little dependence on the surface pressure at which they were formed. SFG spectra of HBMs with a mixed cholesterol/DPPE proximal layer were very similar to the spectra of HBMs with a pure cholesterol proximal layer, although the features in the spectra were more intense than anticipated for a film with half the number of cholesterol molecules, indicating that DPPE did have some effect on the orientation of cholesterol molecules in the film.
Authors:
P J N Kett; M T L Casford; P B Davies
Related Documents :
19183415 - Low-fat oxidation may be a factor in obesity among men with schizophrenia.
19674355 - The effect of low-carbohydrate diet on left ventricular diastolic function in obese chi...
21159315 - Ischemia-modified albumin as an oxidative stress biomarker in obesity.
20002075 - Pharmacotherapy for obesity.
835935 - Plasma glucose levels: long-term effect of diet in the chicago coronary prevention eval...
3428365 - A study of the hepatic lipids during chick embryo development. effect of triiodothyronine.
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2011-5-4
Journal Detail:
Title:  The journal of physical chemistry. B     Volume:  -     ISSN:  1520-5207     ISO Abbreviation:  -     Publication Date:  2011 May 
Date Detail:
Created Date:  2011-5-5     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101157530     Medline TA:  J Phys Chem B     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Affiliation:
Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  All-Optical Control of a Single Plasmonic Nanoantenna-ITO Hybrid.
Next Document:  Effect of Surfactants on Shear-Induced Gelation and Gel Morphology of Soft Strawberry-like Particles...