Nanomaterials for T2 contrast, bone targeting and multimodal imaging

Hochschulschrift

Zusammenfassung: The first part focuses on the magnetic properties and cytocompatibility issues originating from different geometries of ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs), the most common T2 contrast agent used in magnetic resonance imaging (MRI). In order to observe these effects, spherical and tripod shaped USPIONs were synthesized by varying precursor concentration and temperature during synthesis. The superparamagnetic behavior and T2 relaxation values for tripod USPIONs were greater than that for similar shaped tetrapod USPIONs reported in the literature. To investigate the effect on in vitro toxicity the hydrophobic USPIONs (spheres and tripods) were converted into water stable suspensions using a ligand exchange reaction with citric acid while preserving the magnetization and superparamagnetic behavior. The cytocompatibility of both the NP shapes was investigated by using a MTT assay to monitor mitochondrial activity and the induction of reactive oxygen species (ROS) in HeLa (human cervical cancer cells) and Hepa 1-6 (a mouse hepatoma cell line). Furthermore the level of liver enzymes in Hepa 1-6 was quantified. Surprisingly tripods showed lower levels of ROS compared to their spherical counterparts while the induction of liver enzymes and mitochondrial activity was comparable with both particle types. In the second part of the thesis, a polymeric nanoparticle was engineered to target porous bone, containing an MRI and a FMT contrast agent for multimodal visualization. This approach could enable the early detection of bone related diseases, where a change in bone mineral density is involved.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Albert-Ludwigs-Universität Freiburg, Dissertation, 2016

Classification and Topics

• Keyword: Bildgebendes Verfahren ; Ferrite ; Nanopartikel ; Targeted drug delivery ; Kernspintomografie ; Diagnose ; Diagnostik ; Differentialdiagnose ; Pflegediagnose

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2016
• Creator: Wyss, Pradeep P.
• Contributor: Shastri, V. Prasad

Further information

• DOI: 10.6094/UNIFR/11393
• URN: urn:nbn:de:bsz:25-freidok-113936
• Rights: Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 25.03.2025, 1:49 PM CET