title: The role of attached phase soil and sediment organic matter physicochemical properties on fullerene (nC60) attachment.
abstract: Attached phase soil and sediment organic matter is ubiquitous in the subsurface environment, with a tendency to strongly sorb contaminants, and therefore it may play an important role in contaminant transport. In this study, the deposition of C60 nanoparticles onto attached phase Harpeth Humic Acid and Harpeth Fulvic Acid (HHA and HFA) is explored by using a quartz crystal microbalance with dissipation monitoring and systematically varying thermal energy. By comparing the C60 attachment onto HHA and HFA surfaces to that of bare silica and DLVO predictions, we find that the HHA and HFA layers hinder attachment at low temperatures, while HHA enhances attachment at higher temperatures. Based on thermal characterization of the HHA and HFA layers compared to the corresponding attachment trends, the attachment efficiency is strongly correlated with hydration of the layer. Possible mechanisms explaining this phenomenon include water-assisted disruption of polar SOM contacts and hydration-induced swelling of the AP-SOM matrix. Since humic substances typically dominate subsurface organic matter, these results may prove crucial to understanding the complex interactions of engineered nanomaterials in both the natural and engineered environment.
authors.affiliation: Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235, United States. Electronic address: coy.p.mcnew@vanderbilt.edu.
authors.forename: Coy P
authors.initials: CP
authors.lastname: McNew
authors.affiliation: Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235, United States. Electronic address: eugene.j.leboeuf@vanderbilt.edu.
authors.forename: Eugene J
authors.initials: EJ
authors.lastname: LeBoeuf
mesh_terms: D001578:Benzopyrans / Q000737:chemistry*; D055598:Chemical Phenomena; D004785:Environmental Pollutants / Q000737:chemistry*; D037741:Fullerenes / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry*; D006812:Humic Substances; D012822:Silicon Dioxide / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D001578:Benzopyrans; D004785:Environmental Pollutants; D037741:Fullerenes; D006812:Humic Substances; D012987:Soil; D014867:Water; D012822:Silicon Dioxide; C069837:fullerene C60; C005023:fulvic acid
keywords: Fullerene; Fulvic acid; Humic acid; QCM-D; SOM; “C(60)”