Impact of storage conditions and storage time on silver nanoparticles' physicochemical properties and implications for their biological effects

Research output: Contribution to journalArticle


  • E. Izak-nau
  • A. Huk
  • B. Reidy
  • H. Uggerud
  • M. Vadset
  • S. Eiden
  • M. Voetz
  • M. Himly
  • A. Duschl
  • M. Dusinska

Colleges, School and Institutes

External organisations

  • Bayer Technology Services GmbH, Leverkusen
  • Department of Molecular Biology, University of Salzburg, Salzburg
  • Health Effects Laboratory, Department of Environmental Chemistry, NILU-Norwegian Institute for Air Research, Kjeller
  • Centre for BioNano Interactions, School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4
  • Inorganic Group, Department of Environmental Chemistry, NILU-Norwegian Institute for Air Research, Kjeller


It is increasingly recognized that nanoparticles (NPs) can ‘age’ while stored, and that the impact of this may lead to divergent results in terms of the observed toxicity of nominally the same NPs. The main goal of this study was to investigate whether (and to what extent) changes in silver (Ag) NPs' properties occur over time and whether storage of the dispersions under different conditions impacts their stability and ageing mechanism, as a function of the NPs' surface capping/charge. We found that both storage time/conditions and surface chemistry of AgNPs influenced the evolution of the NP properties over time, and that the resulting changes in the NPs' physicochemical properties influenced their toxicity. Observed changes in Ag NPs' toxicity were related to different processes such as NP agglomeration, dissolution, oxidation, capping agent degradation as well attachment of Ag+ ions to container walls. Thus, NP ‘aging’ effects as described here can be a significant contributor to the contradictory toxicity results observed in the literature for identical NPs, and NP ageing should thus be assessed in parallel with toxicity assessment as best practice.


Original languageEnglish
Pages (from-to)84172-84185
JournalRSC Advances
Issue number102
Early online date25 Sep 2015
Publication statusPublished - Sep 2015