Paramagnetic gd-based gold glyconanoparticles as probes for magnetic resonance imaging

Résumé

The present PhD Thesis is focused on the development of paramagnetic Gd-based gold glyconanoparticles (Gd-GNPs), i.e. nanoparticles that present on the same nanometric gold clusters both sugar conjugates and Gd(III) chelates. This work is the continuation of a research line which was started in our group with another PhD Thesis (D. Alcántara Parra) and which was mainly dedicated to the one-pot preparation of Gd-GNPs as new paramagnetic probes for imaging of glioma in mice by Magnetic Resonance Imaging (MRI). The amount of Gd(III) in the GNPs synthesized by this method was not under complete control. In order to solve this problem, a new protocol based on a two-steps synthesis was developed. The preparation / characterization of Gd-GNPs and the comparison of their relaxivity properties with contrast agents in clinical use will be presented together with the use of these Gd-GNPs as contrast agents for the selective labelling of cell surface receptors by MRI. These biofuncional nanomaterials are water soluble, biocompatible and non-toxic to cellular lines.Finally, the application of Gd-GNPs as probes for in vivo MRI of glioma in mice was performed in collaboration with the ¿Grup d¿Aplicacions Biomèdiques de la RMN (GABRMN)¿ at Universitat Autònoma de Barcelona (UAB). Biodistribution studies and toxicological profile were also determined in collaboration with the group CIBBIM-Nanomedicine at the Vall d¿Hebron Hospital (UAB).