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Updated: Sep 29, 2025
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Solubility of Hydrophobic Compounds in Aqueous Solution Using Combinations of Self-assembling Peptide and Amino Acid
Published on: September 20, 2017
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Amino Acids Are Driven to the Interface by Salts and Acidic Environments
Kyle J Angle1, Christopher M Nowak1, Aakash Davasam1
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States.
The Journal of Physical Chemistry Letters
|March 24, 2022
Summary
Amino acids are highly surface active in sea spray aerosols, with salts and low pH increasing their concentration. This impacts aerosol cloud properties and peptide formation.
Area of Science:
- Environmental Chemistry
- Atmospheric Chemistry
- Biogeochemistry
Background:
- Amino acids (AAs) are protein building blocks found in ocean waters.
- AAs are significantly enriched in sea spray aerosols, suggesting surface activity.
Purpose of the Study:
- To investigate the surface activity of amino acids in sea spray aerosols.
- To determine the influence of environmental factors like salts and pH on AA surface behavior.
Main Methods:
- Surface tension measurements
- Infrared reflection-absorption spectroscopy
- Molecular dynamics simulations
Main Results:
- Amino acids exhibit significant surface activity at the air-water interface.
- Salts and low pH increase the surface activity and coverage of hydrophobic AAs.
- Divalent cations (Ca2+, Mg2+) enhance AA surface propensity, especially at neutral pH.
Conclusions:
- Amino acids are concentrated at the surface of sea spray aerosols.
- Increased AA surface concentration affects aerosol cloud activation properties.
- These findings suggest potential for enhanced peptide formation in aerosols.
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