Clay particles destabilize engineered nanoparticles in aqueous environments.
Summary of "Clay particles destabilize engineered nanoparticles in aqueous environments."
Given the ubiquity of natural clay minerals, the most likely interaction of nanoparticles released into an aquatic environment will be with suspended clay minerals. Thus, the transport of engineered nanoparticles in the subsurface and the water column will most likely be altered by their interaction with these minerals. We studied the interactions of two of the most produced nanoparticles, Ag and TiO2, and montmorillonite to determine how heteroaggregation can alter the stability of nanoparticle/clay mineral mixtures. Since at low pH montmorillonite has a negatively charged basal plane and positively charged edges, its interaction with these nanoparticles at different pH lead to unusual behaviors. There are six different interactions for each clay-nanoparticle pair. At pH values below the IEP of montmorillonite edge site, montmorillonite reduced the stability of both negatively charged Ag and positively charged TiO2 nanoparticles. Surprisingly this enhanced coagulation only occurs within an intermediate ionic strength range. The spillover of the montmorillonite basal plane electric double layer to the montmorillonite edge may screen the electrostatic attraction between Ag and the montmorillonite edge at low ionic strength, while a repulsion between TiO2 and montmorillonite face sites may re-stabilize the mixture.
Affiliation
Journal Details
This article was published in the following journal.
Name: Environmental science & technology
ISSN: 1520-5851
Pages:
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22721423
- DOI: http://dx.doi.org/10.1021/es3004427
Medical and Biotech [MESH] Definitions
Nanoparticles
Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.
Metal Nanoparticles
Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.
Magnetite Nanoparticles
Synthesized magnetic particles under 100 nanometers possessing many biomedical applications including DRUG DELIVERY SYSTEMS and CONTRAST AGENTS. The particles are usually coated with a variety of polymeric compounds.
Endosulfan
A polychlorinated compound used for controlling a variety of insects. It is practically water-insoluble, but readily adheres to clay particles and persists in soil and water for several years. Its mode of action involves repetitive nerve-discharges positively correlated to increase in temperature. This compound is extremely toxic to most fish. (From Comp Biochem Physiol (C) 1993 Jul;105(3):347-61)
Elementary Particle Interactions
The interactions of particles responsible for their scattering and transformations (decays and reactions). Because of interactions, an isolated particle may decay into other particles. Two particles passing near each other may transform, perhaps into the same particles but with changed momenta (elastic scattering) or into other particles (inelastic scattering). Interactions fall into three groups: strong, electromagnetic, and weak. (From McGraw-Hill Encyclopedia of Science & Technology, 7th ed)
PubMed Articles
Phase inversion of emulsions containing a lipophilic surfactant induced by clay concentration.
Emulsions stabilized by clay particles and sorbitan monooleate (Span 80) were investigated, and an abnormal phase inversion was observed by increasing the concentration of clay particles in the aqueou...
Engineered nanoparticles and their identification among natural nanoparticles.
The more nanotechnology develops, the more likely the release of engineered nanoparticles into the environment becomes. Due to a huge excess of natural nanoparticles, the identification and quantifica...
Pure as well as organically modified clay minerals are widely applied particles in different research areas. For the incorporation of hydrophobic organically modified clay particles into the hydrogel...
Increasing use of engineered nanoparticles (NPs) is likely to result in release of these particles to the aquatic environment where the NPs may eventually accumulate in sediment. However, little is kn...
Assessment of the behavior and fate of engineered nanoparticles (ENPs) in natural aquatic media is crucial for the identification of environmentally critical properties of the ENPs. Here we present a...
Clinical Trials
The aim of this study is to evaluate the antibacterial activity of crosslinked quaternary ammonium polyethylenimine (PEI) nanoparticles incorporated at 1-2% w/w in a commercial soft liner...
The effect of Antibacterial Nanoparticles, Incorporated in cement, on S.mutans in the margins of provisional restorations is going to be examined clinically by using two kinds of provision...
Testing the Re-Engineered Hospital Discharge
The purpose of this study is to determine if the "Re-Engineered Discharge" will decrease rehospitalization rates and adverse events of patients leaving Boston Medical Center.
Absorption of Brimonidine Ophthalmic Solution in the Aqueous Humor of Cataract Patients
The purpose of this study is to obtain and assay human aqueous samples following pre-operative dosing with 0.1% Brimonidine Purite™ (pH 7.8) or with 0.15% Brimonidine Purite® (pH 7.2) f...
Bioavailability of Bimatoprost Ophthalmic Solution in Human Aqueous.
The purpose of this study is to assay human aqueous for bimatoprost and the presence of any metabolites, especially prostaglandin analogs. Hypothesis:Bimatoprost is not metabolized to a pr...
