Toxicity of functional nano-micro zinc oxide tetrapods: impact of cell culture conditions, cellular age and material properties.
With increasing production and applications of nanostructured zinc oxide, e.g., for biomedical and consumer products, the question of safety is getting more and more important. Different morphologies of zinc oxide structures have been synthesized and accordingly investigated. In this study, we have particularly focused on nano-micro ZnO tetrapods (ZnO-T), because their large scale fabrication has been made possible by a newly introduced flame transport synthesis approach which will probably lead to several new applications. Moreover, ZnO-T provide a completely different morphology then classical spherical ZnO nanoparticles. To get a better understanding of parameters that affect the interactions between ZnO-T and mammalian cells, and thus their biocompatibility, we have examined the impact of cell culture conditions as well as of material properties on cytotoxicity. Our results demonstrate that the cell density of fibroblasts in culture along with their age, i.e., the number of preceding cell divisions, strongly affect the cytotoxic potency of ZnO-T. Concerning the material properties, the toxic potency of ZnO-T is found to be significantly lower than that of spherical ZnO nanoparticles. Furthermore, the morphology of the ZnO-T influenced cellular toxicity in contrast to surface charges modified by UV illumination or O2 treatment and to the material age. Finally, we have observed that direct contact between tetrapods and cells increases their toxicity compared to transwell culture models which allow only an indirect effect via released zinc ions. The results reveal several parameters that can be of importance for the assessment of ZnO-T toxicity in cell cultures and for particle development.
Institute of Toxicology and Pharmacology for Natural Scientists, Christiana Albertina University Kiel, Kiel, Germany.
Heike
H
Papavlassopoulos
Functional Nanomaterials, Institute for Materials Science, Christiana Albertina University Kiel, Kiel, Germany.
Yogendra K
YK
Mishra
Functional Nanomaterials, Institute for Materials Science, Christiana Albertina University Kiel, Kiel, Germany.
Sören
S
Kaps
Functional Nanomaterials, Institute for Materials Science, Christiana Albertina University Kiel, Kiel, Germany.
Ingo
I
Paulowicz
Nanochemistry and Nanoengineering, Institute for Materials Science, Christiana Albertina University Kiel, Kiel, Germany.
Ramzy
R
Abdelaziz
Nanochemistry and Nanoengineering, Institute for Materials Science, Christiana Albertina University Kiel, Kiel, Germany ; Nanochemistry and Nanoengineering, Institute of Polymer Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany.
Mady
M
Elbahri
Institute of Toxicology and Pharmacology for Natural Scientists, Christiana Albertina University Kiel, Kiel, Germany.
Edmund
E
Maser
Functional Nanomaterials, Institute for Materials Science, Christiana Albertina University Kiel, Kiel, Germany.
Rainer
R
Adelung
Institute of Toxicology and Pharmacology for Natural Scientists, Christiana Albertina University Kiel, Kiel, Germany ; ZEBET - Alternative Methods to Animal Experiments, Federal Institute for Risk Assessment, Berlin, Germany.
Claudia
C
Röhl
D002452:Cell Count; D018929:Cell Culture Techniques; D016923:Cell Death / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016922:Cellular Senescence / Q000187:drug effects*; D020405:Dermis / Q000166:cytology; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D053758:Nanoparticles / Q000633:toxicity* / Q000648:ultrastructure; D010316:Particle Size; D015034:Zinc Oxide / Q000737:chemistry* / Q000633:toxicity*
D015034:Zinc Oxide