Skip to Content
Merck
  • Tracing bioavailability of ZnO nanoparticles using stable isotope labeling.

Tracing bioavailability of ZnO nanoparticles using stable isotope labeling.

Environmental science & technology (2012-10-12)
Fiona Larner, Yuktee Dogra, Agnieszka Dybowska, Julia Fabrega, Björn Stolpe, Luke J Bridgestock, Rhys Goodhead, Dominik J Weiss, Julian Moger, Jamie R Lead, Eugenia Valsami-Jones, Charles R Tyler, Tamara S Galloway, Mark Rehkämper
ABSTRACT

Zinc oxide nanoparticles (ZnO NPs) are widely used in commercial products and knowledge of their environmental fate is a priority for ecological protection. Here we synthesized model ZnO NPs that were made from and thus labeled with the stable isotope (68)Zn and this enables highly sensitive and selective detection of labeled components against high natural Zn background levels. We combine high precision stable isotope measurements and novel bioimaging techniques to characterize parallel water-borne exposures of the common mudshrimp Corophium volutator to (68)ZnO NPs, bulk (68)ZnO, and soluble (68)ZnCl(2) in the presence of sediment. C. volutator is an important component of coastal ecosystems where river-borne NPs will accumulate and is used on a routine basis for toxicity assessments. Our results demonstrate that ionic Zn from ZnO NPs is bioavailable to C. volutator and that Zn uptake is active. Bioavailability appears to be governed primarily by the dissolved Zn content of the water, whereby Zn uptake occurs via the aqueous phase and/or the ingestion of sediment particles with adsorbed Zn from dissolution of ZnO particles. The high sorption capacity of sediments for Zn thus enhances the potential for trophic transfer of Zn derived from readily soluble ZnO NPs. The uncertainties of our isotopic data are too large, however, to conclusively rule out any additional direct uptake route of ZnO NPs by C. volutator.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Zinc chloride solution, 1.0 M in diethyl ether
Sigma-Aldrich
Zinc chloride, reagent grade, ≥98%
Sigma-Aldrich
Zinc chloride solution, 0.5 M in THF
Sigma-Aldrich
Zinc chloride, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥98%
Sigma-Aldrich
Zinc chloride solution, 1.9 M in 2-methyltetrahydrofuran
Sigma-Aldrich
Zinc chloride, 99.999% trace metals basis
Sigma-Aldrich
Zinc chloride, AnhydroBeads, amorphous, −10 mesh, 99.999% trace metals basis
Sigma-Aldrich
Zinc chloride, AnhydroBeads, amorphous, −10 mesh, 99.99% trace metals basis
Sigma-Aldrich
Zinc chloride, anhydrous, powder, ≥99.995% trace metals basis
Sigma-Aldrich
Zinc chloride, ACS reagent, ≥97%
Sigma-Aldrich
Zinc chloride, puriss., meets analytical specification of Ph. Eur., BP, USP, 98-100.5%
Sigma-Aldrich
Zinc chloride 0.1 M solution
Sigma-Aldrich
Zinc chloride, BioReagent, for molecular biology, suitable for cell culture, suitable for insect cell culture