131
Views
6
CrossRef citations to date
0
Altmetric
Articles

Three-layered silver nanoparticles to trace dissolution and association to a green alga

ORCID Icon, , , , &
Pages 1149-1160 | Received 11 Feb 2019, Accepted 02 Jun 2019, Published online: 26 Jul 2019
 

Abstract

Core-shell silver nanoparticles (NPs) consisting of an inner Ag core and successive layers of Au and Ag (Ag@Au@Ag) were used to measure the simultaneous association of Ag NPs and ionic Ag by the green alga Chlamydomonas (C.) reinhardtii. Dissolution of the inner Ag core was prevented by a gold (Au) layer, while the outer Ag layer was free to dissolve. In short-term experiments, we exposed C. reinhardtii to a range of environmentally realistic Ag concentrations added as AgNO3 or as NPs. Results provide three lines of evidence for the greater cell-association of NPs compared to dissolved Ag over the concentration range tested, assuming that cell-association comprises both uptake and adsorption. First, the cell-association rate constants (kuw) for total Ag (AgNP+D), NPs (AgNP) and AuNP were similar and 2.2-fold higher than the one from AgD exposure, suggesting predominant association of the particles over the dissolved form. Second, model calculations based on Ag fluxes suggested that only 6–33% of algal burden was from AgD. Third, the significantly lower AgNP/Au ratio measured with the algae after exposure (2.1 ± 0.1) compared to the AgNP/Au ratio of the NPs in the media (2.47 ± 0.05) suggests cell-association of NPs depleted in Ag. Core–shell NPs provide an innovative tool to understand NP behavior and to directly delineate Ag accumulation from ion and NPs in aquatic systems.

Acknowledgements

Natasha Franklin is acknowledged for manuscript review and comments. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the US Government.

Disclosure statement

The authors declare that there is no conflict of interest regarding the publication of this article.

Additional information

Funding

Funding was provided by the Fonds de Recherche Nature et Technologies du Québec, the US National Science Foundation, the National Research Program of the US Geological Survey, and from the University of South Carolina (Smartstate Center for Environmental Nanoscience and Risk and the ASPIRE grant).

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 65.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 547.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.