Open AccessCerium oxide nanoparticles transformation at the root–soil interface of barley (Hordeum vulgareL.)
Author(s) -
Cyren M. Rico,
Mark G. Johnson,
Matthew A. Marcus
Publication year - 2018
Publication title -
environmental science. nano
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.881
H-Index - 67
eISSN - 2051-8161
pISSN - 2051-8153
DOI - 10.1039/c8en00316e
Subject(s) - hordeum vulgare , cerium oxide , cerium , chemistry , genetic algorithm , nanoparticle , environmental chemistry , transformation (genetics) , oxide , nuclear chemistry , botany , materials science , inorganic chemistry , nanotechnology , poaceae , biology , biochemistry , organic chemistry , evolutionary biology , gene
The transformation of cerium oxide nanoparticles (CeO 2 -NPs) in soil and its role in plant uptake is a critical knowledge gap in the literature. This study investigated the reduction and speciation of CeO 2 -NPs in barley ( Hordeum vulgare L.) cultivated in soil amended with 250 mg CeO 2 -NPs kg -1 soil. Synchrotron micro-X-ray fluorescence (μXRF) was employed for spatial localization and speciation of CeO 2 -NPs in thin sections of intact roots at the soil-root interface. Results revealed that Ce was largely localized in soil and at the root surface in nanoparticulate form (84-89%). However, a few hot spots on root surfaces revealed highly significant reduction (55-98%) of CeO 2 -NPs [Ce(IV)] to Ce(III) species. Interestingly, only roots in close proximity to hot spots showed Ce uptake which was largely CeO 2 (89-91%) with very little amount Ce(III) (9-10%). These results suggest that the reduction of CeO 2 -NPs to Ce(III) is needed to facilitate uptake of Ce.