Jump to main content
Jump to site search


Transformation and uptake of silver nanoparticles and silver ions in rice plant (Oryza sativa L.): the effect of iron plaque and dissolved iron

Author affiliations

Abstract

The wide use of silver ions (Ag+) and silver nanoparticles (AgNPs) and their inevitable release into the environment have caused great concern over their environmental and health risks. The understanding of their uptake and accumulation by plants, especially food crops, is important to evaluate their risks. We reported herein the distinct accumulation and translocation characteristics of Ag+ and AgNPs in a rice plant (Oryza sativa L.) at exposure doses of 2, 5, 10, and 20 mg L−1, as well as the critical impact of iron plaque on their assimilation by the plant. As revealed by silver K-edge X-ray absorption near-edge structure (XANES), Ag+ in/on the roots was exclusively transformed into AgCl with Cl in hydroponic medium. As a result, AgCl maintained Ag+ on the root surface, lowering its bioavailability and translocation (with translocation factors, TFs, from 0.44 × 10−3 to 1.79 × 10−3). On the contrary, AgNPs were assimilated and translocated more effectively (with TFs from 2.44 × 10−3 to 1.23 × 10−2) in comparison to Ag+, although a fraction was transformed into ionic silver species. XANES demonstrated that the iron plaque present on the rice roots could oxidize AgNPs into ionic Ag species, such as AgCl and Ag+–thiol complexes, and increase the uptake and translocation of silver in the rice plant. Compared to iron plaque, dissolved iron was less effective in oxidizing AgNPs. Our findings highlighted the importance of Ag species interconversion and iron plaque in the uptake and translocation of Ag, providing useful data for an improved risk assessment of AgNPs and Ag+ under environmental scenarios.

Graphical abstract: Transformation and uptake of silver nanoparticles and silver ions in rice plant (Oryza sativa L.): the effect of iron plaque and dissolved iron

Back to tab navigation

Supplementary files

Article information


Submitted
15 Nov 2019
Accepted
23 Dec 2019
First published
26 Dec 2019

Environ. Sci.: Nano, 2020, Advance Article
Article type
Paper

Transformation and uptake of silver nanoparticles and silver ions in rice plant (Oryza sativa L.): the effect of iron plaque and dissolved iron

Q. Yang, W. Xu, G. Liu, M. Song, Z. Tan, Y. Mao, Y. Yin, Y. Cai, J. Liu and G. Jiang, Environ. Sci.: Nano, 2020, Advance Article , DOI: 10.1039/C9EN01297D

Social activity

Search articles by author

Spotlight

Advertisements