Linked Life Data

15638611

Source:http://linkedlifedata.com/resource/pubmed/id/15638611

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-1-10
pubmed:abstractText
Despite extensive study the phase behavior of phospholipid monolayers at an air-water interface is still not fully understood. In particular recent vibrational sum-frequency generation (VSFG) spectra of DPPC monolayers as a function of area density show a sharp transition in the order of the lipid chains at 1.10 nm2/molecule. This is in a region where the lateral pressure as a function of area is effectively constant. We have investigated the nature of this transition by studying the phase behavior of DPPC monolayers as a function of area density using molecular-dynamics simulations. The changes in order within the monolayer as a function of area density correlate well with the experimental signal. At 0.58 nm2/molecule we observe the onset of lateral separation of highly ordered and disordered lipids, indicating the coexistence of a gel-like liquid condensed and a fluidlike liquid expanded phase. At 0.97 nm2/molecule the monolayer ruptures, marking the onset of the liquid-gas (G) coexistence region. This is much earlier than suggested by fluorescence microscopy results and implies that at the point of rupture, the initial pores have an equilibrium size smaller than approximately 500 nm in diameter. The rupture of the monolayer leads to a sharp increase in the overall lipid order that explains the sharp transition observed in the VSFG measurements. VSFG measurements thus may represent a sensitive means to determine the onset of the liquid-gas (G) coexistence region for such systems.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9606
pubmed:author
pubmed:copyrightInfo
2005 American Institute of Physics.
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
122
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
024704
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Simulation studies of pore and domain formation in a phospholipid monolayer.
pubmed:affiliation
Department of Biophysical Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands. v.knecht@chem.rug.nl
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't