Erschienen:
[Erscheinungsort nicht ermittelbar]: HAL CCSD, 2022
Sprache:
Französisch
Entstehung:
Hochschulschrift:
Dissertation, HAL CCSD, 2022
Anmerkungen:
Beschreibung:
The birth of magnetic resonance imaging (MRI) marks a major advance in the history of radiology. For almost 50 years, MRI has become an indispensable imaging and diagnostic tool. One of the main objectives is now to obtain better contrast and sensitivity in order to understand the biochemical and biological phenomena for better patient diagnostics, this is called molecular imaging. The principle of this discipline is to detect specific molecules, such as DNA sequences, cell markers, enzymes, reactive species . It will then be possible, for example, to detect nascent cancers. The specific molecules are often present in very small quantities in the tissues and require imaging techniques with very good sensitivity. MRI has very good resolution but suffers from a lack of sensitivity. This is why contrast agents are added in order to gain in sensitivity. Conversely, optical imaging benefits from increased sensitivity but does not allow in-depth study. By coupling these two techniques, it would then be possible to study with precision the molecular mechanisms deep within the tissues.This thesis project was born in order to develop contrast agents based on lanthanides and non-innocent ligands that specifically respond to oxidative stress. The detection of this oxidative stress by several different techniques could be achieved using a bimodal probe which would combine the benefits of MRI and optical imaging, as good resolution and high sensitivity. In order to gain even more sensitivity, a new technique derived from MRI, called CEST" for Chemical Exchange Saturation Transfer was born.The aim of this thesis is to provide the proof of concept of bimodal probes for the detection of reactive oxygen species by magnetic imaging and optical imaging techniques. For this, new families of lanthanide complexes with a radical or pro-radical ligand have been chemically synthesized and have been studied by different spectroscopic and electrochemical techniques. These analyzes validated the proof of concept by creating a bimodal ..."