Physically self-assembled monolayers (PSAMs) of lecithin lipids at hydrophilic silicon oxide interfaces

A new method of making physically self-assembled monolayers (PSAMs) on hydrophilic solid surfaces is presented. This method uses a mixture of a nonpolar solvent, such as hexane, and a strong polar solvent, such as ethanol, to dissolve the lipids. The deposition of two lecithin lipids, dipalmitoylpho...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 22(2006), 4 vom: 14. Feb., Seite 1609-18
1. Verfasser: Phang, Tze-Lee (VerfasserIn)
Weitere Verfasser: Franses, Elias I
Format: Aufsatz
Sprache:English
Veröffentlicht: 2006
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Membranes, Artificial Phosphatidylcholines 1,2-dilauroylphosphatidylcholine 18285-71-7 1,2-Dipalmitoylphosphatidylcholine 2644-64-6 Silicon Dioxide 7631-86-9
Beschreibung
Zusammenfassung:A new method of making physically self-assembled monolayers (PSAMs) on hydrophilic solid surfaces is presented. This method uses a mixture of a nonpolar solvent, such as hexane, and a strong polar solvent, such as ethanol, to dissolve the lipids. The deposition of two lecithin lipids, dipalmitoylphosphatidylcholine (DPPC) and dilauroylphosphatidylcholine (DLPC), has been studied. These lipids physically self-assemble, or adsorb, onto hydrophilic silicon oxide/silicon surfaces when such surfaces are in contact with the lipid solution. The adsorbed layers were probed with ex-situ attenuated total reflection infrared (ATR-IR) spectroscopy, ellipsometry, contact angle measurements, and atomic force microscopy (AFM). The thicknesses of the adsorbed monolayers are about 2.8 +/- 0.2 nm for DPPC and 2.0 +/- 0.2 nm for DLPC, as determined by ellipsometry and AFM. Smooth, uniform monolayers of controlled surface density are formed. The surface density of adsorbed layers is comparable to those of close-packed lipid monolayers, as calculated from the ellipsometry and ATR-IR results. Producing controlled-thickness monolayers has applications in boundary lubrication, biomaterials, sensor technologies, and electronics. The method can be used for depositing many biological surfactants or lipids without the need to modify these surfactants chemically to form chemical bonds with the surfaces, as required by the usual chemical SAMs. Moreover, the new method has several advantages compared to the Langmuir-Blodgett (LB) method
Beschreibung:Date Completed 09.05.2007
Date Revised 07.02.2006
published: Print
Citation Status MEDLINE
ISSN:1520-5827