Characterization of seawater and aerosol particle surfactants using solid phase extraction and mass spectrometry


Amanda A. Frossard , Tret C. Burdette

DOI:10.1016/j.jes.2021.01.026

Received September 12, 2020,Revised , Accepted January 22, 2021, Available online March 09, 2021

Volume 33,2021,Pages 164-174

Surface-active organic molecules (surfactants) may influence the ability of an aerosol particle to act as a cloud condensation nuclei by reducing its surface tension. One source of organic mass in aerosol particles, which may also contain surfactants, is bubble bursting on the sea surface. In order to directly compare these molecules in the ocean and aerosol particles, we developed a method using multiple solid phase extractions and high resolution mass spectrometry to characterize surface active organic molecules in both. This method has extraction efficiencies greater than 85%, 75%, and 60% for anionic, cationic, and nonionic surfactant standards, respectively. In this study, we demonstrate the presence of three ionic classes of surface active organics in atmospheric aerosol particles and estuarine water from Skidaway Island, GA. With this extraction method, organic molecules from both estuarine water and atmospheric aerosol particles significantly reduced surface tension of pure water (surface tension depression of ~ 18 mN/m) and had high ratios of hydrogen to carbon (H/C) and low ratios of oxygen to carbon (O/C), indicative of surfactants. While previous work has observed a larger fraction of anionic surface active organics in seawater and marine aerosol particles, here we show cationic surface active organics may make up a large fraction of the total surface active molecules in estuarine water (43%–47%).

Copyright © Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.京ICP备05002858号-3