Composition of supported model membranes determined by neutron reflection
We have investigated the formation of supported bilayers by coadsorption of dipalmitoyl phosphatidylcholine (DPPC) with the nonionic surfactant beta-D-dodecyl maltoside. The adsorption of mixed phospholipid-surfactant micelles on hydrophilic silica surfaces at 25 degrees C was followed as a function...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 21(2005), 7 vom: 29. März, Seite 2827-37 |
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1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2005
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Comparative Study Journal Article Research Support, Non-U.S. Gov't Glucosides Lipid Bilayers Phosphatidylcholines dodecyl maltoside 69227-93-6 Cholesterol 97C5T2UQ7J |
Zusammenfassung: | We have investigated the formation of supported bilayers by coadsorption of dipalmitoyl phosphatidylcholine (DPPC) with the nonionic surfactant beta-D-dodecyl maltoside. The adsorption of mixed phospholipid-surfactant micelles on hydrophilic silica surfaces at 25 degrees C was followed as a function of bulk concentration by neutron reflection. Using chain-deuterated d(25)-beta-D-dodecyl maltoside and d(62)-DPPC, we demonstrate that it is possible to determine the composition of the bilayers at each stage of a sequential dilution process, which enriches the adsorbed layer in phospholipid and leads to complete elimination of the surfactant. The final supported bilayers have thicknesses of 51 +/- 3 A and are stable to heating to 37 degrees C once all surfactant has been removed, and the structures agree well with other published data on DPPC supported bilayers. The coadsorption of cholesterol in a DPPC-surfactant mixture was also achieved, and the location and volume fraction of cholesterol in the DPPC bilayer was determined. Cholesterol is located in a 18 +/- 1 A thick layer below the lipid headgroup region and leads to an increased bilayer thickness of 58 +/- 2 A at 26 mol % of cholesterol |
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Beschreibung: | Date Completed 14.06.2006 Date Revised 21.11.2013 published: Print Citation Status MEDLINE |
ISSN: | 1520-5827 |