Stability and toxicity of ZnO quantum dots: Interplay between nanoparticles and bacteria

Xavier Bellanger (1) , Patrick Billard (2) , Raphaël Schneider (3) , Lavinia Balan (4) , Christophe Merlin (1)

1 LCPME - Laboratoire de Chimie Physique et Microbiologie pour l'Environnement
2 LIEC - Laboratoire Interdisciplinaire des Environnements Continentaux
3 LRGP - Laboratoire Réactions et Génie des Procédés
4 IS2M - Institut de Science des Matériaux de Mulhouse

The toxicity of quantum dots (QDs) has been commonly attributed to the release of metal ions from thecore as well as to the production of reactive oxygen species. However, the information related to the stability of the nanoparticles are relatively scarce although this parameter may strongly influence their toxicity. The stability of aminosilane-capped ZnO QDs, here used as model nanoparticles, was investigated by inductively coupled plasma-optical emission spectrometer (ICP-OES) and whole cell biosensors using a dialysis setup to separate the QDs from the leaked Zn2+ ions. The integrity of the ZnO QDs appeared strongly affected by their dilution in aqueous medium, whereas the nanoparticles were slightly stabilized by bacteria. Our results demonstrate some inadequacy between the implementation and use of whole cell biosensors, and the monitoring of metal release from QDs.

Mots clés: ZnO QDs stability; Zn2+ bioavailability; QDs toxicity; Escherichia coli; Cupriavidus metallidurans

Domaines: Matériaux

Xavier Bellanger, Patrick Billard, Raphaël Schneider, Lavinia Balan, Christophe Merlin. Stability and toxicity of ZnO quantum dots: Interplay between nanoparticles and bacteria. Journal of Hazardous Materials, 2015, 283, pp.110-116. ⟨10.1016/j.jhazmat.2014.09.017⟩. ⟨hal-01069257⟩