title: Interactions of graphene oxide nanomaterials with natural organic matter and metal oxide surfaces.
abstract: Interactions of graphene oxide (GO) nanomaterials with natural organic matter (NOM) and metal oxide surfaces were investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D). Three different types of NOM were studied: Suwannee River humic and fulvic acids (SRHA and SRFA) and alginate. Aluminum oxide surface was used as a model metal oxide surface. Deposition trends show that GO has the highest attachment on alginate, followed by SRFA, SRHA, and aluminum oxide surfaces, and that GO displayed higher interactions with all investigated surfaces than with silica. Deposition and release behavior of GO on aluminum oxide surface is very similar to positively charged poly-L-lysine-coated surface. Higher interactions of GO with NOM-coated surfaces are attributed to the hydroxyl, epoxy, and carboxyl functional groups of GO; higher deposition on alginate-coated surfaces is attributed to the rougher surface created by the extended conformation of the larger alginate macromolecules. Both ionic strength (IS) and ion valence (Na(+) vs Ca(2+)) had notable impact on interactions of GO with different environmental surfaces. Due to charge screening, increased IS resulted in greater deposition for NOM-coated surfaces. Release behavior of deposited GO varied significantly between different environmental surfaces. All surfaces showed significant release of deposited GO upon introduction of low IS water, indicating that deposition of GO on these surfaces is reversible. Release of GO from NOM-coated surfaces decreased with IS due to charge screening. Release rates of deposited GO from alginate-coated surface were significantly lower than from SRHA and SRFA-coated surfaces due to trapping of GO within the rough surface of the alginate layer.
authors.affiliation: National Research Council Research Associate, Athens, Georgia 30605, United States.
authors.forename: Indranil
authors.initials: I
authors.lastname: Chowdhury
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Duch
authors.forename: Nikhita D
authors.initials: ND
authors.lastname: Mansukhani
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hersam
authors.forename: Dermont
authors.initials: D
authors.lastname: Bouchard
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000537:Aluminum Oxide / Q000737:chemistry*; D001578:Benzopyrans / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry* / Q000633:toxicity; D006812:Humic Substances / Q000032:analysis*; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000633:toxicity; D009994:Osmolar Concentration; D058525:Quartz Crystal Microbalance Techniques; D045483:Rivers / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000633:toxicity
chemical_list: D000464:Alginates; D001578:Benzopyrans; D006812:Humic Substances; D014874:Water Pollutants, Chemical; D012822:Silicon Dioxide; D006108:Graphite; D000537:Aluminum Oxide; C005023:fulvic acid