title: Influence of surface functionalization and particle size on the aggregation kinetics of engineered nanoparticles.
abstract: In an effort to minimize the impact on the environment or improve the properties of choice, most engineered nanoparticles used for commercial applications are surface functionalized. The release of these functionalized engineered nanoparticles (FENPs) into the environment can be either deliberate or accidental. Scientific research to date has tended to focus on evaluating the toxicity of FENPs, with less attention being given to exposure assessments or to the study of their general behavior in natural environments. We have therefore investigated the effects of environmental parameters such as pH, NaCl concentration, and natural organic matter concentration on the aggregation kinetics of FENPs with time resolved dynamic light scattering, using functionalized gold nanoparticles (FAuNPs) as a representative of these particles. We also investigated the effects of average particle size, the type of surface capping agent, and particle concentration on FAuNP aggregation kinetics. Our results show that the physico-chemical properties of the capping agent have a greater influence on the aggregation behavior of FAuNPs than either their core composition or their particle size.
authors.affiliation: Department of Environmental Geosciences, University of Vienna, Althanstrasse 14 UZAII, A-1090 Vienna, Austria.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Liu
authors.forename: Samuel
authors.initials: S
authors.lastname: Legros
authors.forename: Guibin
authors.initials: G
authors.lastname: Ma
authors.forename: Jonathan G C
authors.initials: JG
authors.lastname: Veinot
authors.forename: Frank
authors.initials: F
authors.lastname: von der Kammer
authors.forename: Thilo
authors.initials: T
authors.lastname: Hofmann
mesh_terms: D019343:Citric Acid / Q000737:chemistry; D004738:Engineering; D005227:Fatty Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D010316:Particle Size; D012965:Sodium Chloride / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties
chemical_list: C505222:11-mercaptoundecanoic acid; D005227:Fatty Acids; D013438:Sulfhydryl Compounds; D019343:Citric Acid; D012965:Sodium Chloride