Interaktion von Nanopartikeln mit immortalisierten Zelllinien und Stammzellen

Abstract

The influence of the polymer of the nanoparticle on the uptake in the cell was investigated with methacrylate nanoparticles with different polymer side chains, but equal in other particle characteristics (size, surfactant load). The influence of the Tg of the particles plays a crucial role on the cellular uptake of the particles. Particles with a glass transition point below the cell incubation temperature showed a better uptake in cells. The influence of functionalization was investigated with phosphonate functionalized particles in cell culture. The uptake, toxicity and the influence on the differentiation of stem cells was investigated closely in this thesis. MSC were differentiated in the presence of particles to the osteogenic, chondrogenic and adipogenic lineage. There was no toxicity and influence on the differentiation potential of the MSC in presence of the particles even after more than one month. Phosphonate groups allow the binding of particles to titanium surfaces. Coated surfaces were preferred for growth of MSC. Degradable capsules allow the disposal of active components in the cell. PBCA capsules containing fluorescent labeled oligonucleotides were used. It could be shown that these capsules were efficiently token up by the cells and didn’t show any toxic effect in cells. The PBCA capsules are able to release their load in cells. In this study we discovered the staining of mitochondria by CY5-labeled oligonucleotides. This was compared to commercial staining methods. Indeed the staining of CY5-labelled oligonucleotides took a little bit longer than the commercial one, but it could be used during a long time observation of cells without a negative influence on the cells. This method created a new cost-efficient alternative in the growing important sector of fluorescence analysis of cells. In addition it is a good and easy method to stain mitochondria over long time periods without any toxic effects.