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Gewählte Doctoral Thesis:

Noga Gal (2018): Superparamagnetic Iron Oxide Core- shell Nanoparticles; Stability and Interactions in Biological Environments.
Doctoral Thesis - Institut für Biologisch inspirierte Materialien, BOKU-Universität für Bodenkultur, pp 208. UB BOKU obvsg FullText

Data Source: ZID Abstracts
Abstract:
Superparamagnetic iron oxide nanoparticles (SPION) with hydrodynamic sizes <30 nm are promising for use in medicine. Their inherent biocompatibility combined with their superparamagnetism make them great candidates for many applications. Understanding of the correlation between SPION colloidal properties and in vivo performance is still poor. This can mainly be blamed on a lack of controlled nanoparticle model systems and a lack of comprehensive characterization of their interaction with biological colloids. We investigate the colloidal properties and interactions with biomolecules and cells of SPION with precise control over size and shape. Interactions of SPION with different core sizes and grafted with hydrophilic poly(ethylene glycol) (PEG) brushes were investigated using QCM-D and calorimetry, and in vitro testing of cell toxicity, barrier crossing and uptake was performed. A weak correlation between core size and protein, lipid membrane and cell activity was found. This was attributed to small cores having higher curvature and therefore a less dense and thinner PEG brush. Further examination of the same SPION grafted with brushes of thermoresponsive polymer confirmed the correlation of a dense polymer brush controlling colloidal stability with low cell uptake and it demonstrated the importance of shell hydration to retain and in situ control this ability. Finally, a system of larger NP for theranostic drug delivery, namely fluorescent polymersomes incorporating hydrophobic SPION in the vesicle membrane, were investigated to track their uptake into the cell through the lysosome. In summary, the combination of carefully designed core-shell SPION and the battery of new characterization methods introduced in this thesis sheds new light on the performance of polymer-grafted nanoparticles in biological dispersions and paints a hopeful picture of the possibility to design and synthesize such particles with a controlled fate also in vivo.

Betreuer: Reimhult Erik
1. Berater: Kasper Cornelia
2. Berater: Sleytr Uwe B.

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