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Updated: May 26, 2026
09:35
Dispersion of Nanomaterials in Aqueous Media: Towards Protocol Optimization
Published on: December 25, 2017
Aggregation kinetics and dissolution of coated silver nanoparticles.
Xuan Li1, John J Lenhart, Harold W Walker
1Department of Civil and Environmental Engineering and Geodetic Science, The Ohio State University, Columbus, Ohio 43210, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 14, 2011
Summary
The study investigated how coating agents affect silver nanoparticle stability in water. Tween 80 significantly enhanced nanoparticle stability, preventing aggregation, while citrate and SDS showed minimal protective effects on these nanoparticles.
Area of Science:
- Environmental chemistry
- Nanotechnology
- Materials science
Background:
- Understanding the environmental fate of manufactured nanomaterials is crucial.
- Stabilizing agents significantly influence nanoparticle behavior in aqueous systems.
- Silver nanoparticles (AgNPs) are widely used, necessitating studies on their environmental impact.
Purpose of the Study:
- To evaluate the aggregation and dissolution of uncoated and coated silver nanoparticles (AgNPs) using common coating agents.
- To assess the influence of trisodium citrate, sodium dodecyl sulfate (SDS), and Tween 80 on AgNP stability in various electrolyte conditions.
- To determine the role of coating agents in the environmental fate of AgNPs in aquatic systems.
Main Methods:
- Dynamic light scattering (DLS) was used to measure early-stage aggregation kinetics.
- Experiments were conducted across a range of electrolyte types (NaCl, NaNO3, CaCl2) and concentrations.
- Electrophoretic mobility measurements were used to assess surface charge and steric interactions.
Main Results:
- Aggregation of uncoated, citrate-coated, and SDS-coated AgNPs was consistent with Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, with similar critical coagulation concentrations (CCC).
- Tween 80-coated AgNPs exhibited significantly enhanced stability, with no aggregation observed up to 1 M NaNO3.
- SDS and Tween 80 coatings inhibited AgNP dissolution and imparted steric stabilization, unlike citrate coating.
Conclusions:
- Coating agents play a critical role in determining the aggregation and dissolution behavior of silver nanoparticles in aquatic environments.
- Tween 80 provides substantial steric stabilization, preventing aggregation and influencing the environmental fate of AgNPs.
- The choice of coating agent can significantly alter the stability and behavior of nanomaterials in water, impacting their environmental persistence and transport.
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