Differential analysis of the role of surface properties and cellular uptake of metal oxides in their nanoform for their cytocompatibility by means of synthesized micro-nanostructures

• Applicants: Professor Dr. Rainer Adelung; Privatdozentin Dr. Claudia Röhl
• Subject Area: Public Health, Healthcare Research, Social and Occupational Medicine
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 235690182

Increasing use of nanomaterials in consumer products, medicine and the environment involves due to new material properties new benefits but also risks. The small particle size permits uptake into cells and passing body barriers. Furthermore, the relatively large and active surface of nanoparticles referring to their mass potentiates their possible interactions with cell- and tissue structures, which might induce or enhance unwanted effects. Only an in-depth understanding of these interactions will make it possible to utilise the big potential and to reduce health risk at the same time.Metal oxides are frequently used for nanomaterials as the synthesis is a relatively fast, simple and cheap process and many variable material properties can achieved. The goal of the submitted proposal is to examine the meaning of cellular uptake and surface properties of metal oxide nanomaterials for their toxicity in various cell culture models to identify those material structures with minimal potential of toxicity. Therefore, changes of cell functions induced by conventional metal oxide nanoparticles, which can be taken up by cells, and special metal oxide micro-nanostructures having the same surface area, but cannot be taken up by cells, will be compared. The micro-nanostructures are synthesized in our lab by flame transport synthesis and consist typically of a micrometer-sized nucleus with multiple nano-sized processes.Sublethal concentrations of metal oxides will be used in cell culture models of human cell lines derived from barrier organs (intestine, lung, skin) and immunocompetent cells to examine pathologically relevant effects like viability, inflammation, oxidative stress or altered cell proliferation.Comparison of toxicological effects of cell-internalized nanoparticles and non-internalized micro-nanostructures will help to derive the relevance of cellular uptake for the toxicity of metal oxides in their nanosize. This will be possible as the surface area in the models can be held constant in both systems, because the normally dependent variables of cellular particle uptake and particle surface area (via the particle diameter) can be uncoupled despite of continued direct cell contact.Moreover, the impact of material surface properties on biological effects of micro-nanostructured metal oxides, which we are able to modify systematically in our lab will be examined.Our findings will contribute to understand toxicological mechanisms of nanomaterials and will help material scientists to consider possible toxicological effects already during the development of metal oxide nanostructures.

• DFG Programme: Research Grants