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Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
Competition between atmospherically relevant fatty acid monolayers at the air/water interface
Laura F Voss1, Christopher M Hadad, Heather C Allen
1Department of Chemistry, The Ohio State University, 100 West 18 Avenue, Columbus, 43210, USA.
The Journal of Physical Chemistry. B
|September 29, 2006
Summary
Fatty acids at the air/water interface compete and oxidize. Less soluble fatty acids reform at the surface after more soluble oxidized fatty acids are removed, impacting aerosol composition.
Area of Science:
- Environmental Chemistry
- Surface Science
- Spectroscopy
Background:
- Fatty acids are key components of atmospheric aerosols.
- Understanding their behavior at the air/water interface is crucial for atmospheric chemistry.
- Competition and oxidation dynamics influence aerosol properties.
Purpose of the Study:
- To investigate the competitive adsorption and oxidation of fatty acids at the air/water interface.
- To elucidate the mechanisms governing surfactant replacement and reformation on aerosol surfaces.
- To understand the fate of fatty acids in atmospheric aerosols.
Main Methods:
- Utilized surface-specific, broad-bandwidth, sum frequency generation (SFG) spectroscopy.
- Studied monolayers of oleic acid and deuterated palmitic acid at the air/water interface.
- Investigated the effects of ozone-induced oxidation on fatty acid monolayers.
Main Results:
- Oleic acid replaced deuterated palmitic acid at the air/water interface.
- Oxidation of oleic acid produced more water-soluble products.
- The less soluble palmitic acid monolayer reformed at the surface after oleic acid oxidation.
Conclusions:
- Surface surfactants on fat-coated aerosols are primarily oxidized acyl chains.
- Less soluble fatty acids are only present after more soluble species are removed from the aqueous subphase.
- Surface replacement and atmospheric oxidation dictate the composition of aerosol surfactants.
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