Physical Sciences and Mathematics Commons^™

Synthesis And Characterization Of New Gd3+-Containing Complexes As Potential Targeted Contrast Agents For Magnetic Resonance Imaging, Sashiprabha Manjari Vithanarachchi

Wayne State University Dissertations

The focus of the research described in this thesis is the study of chemistry relevant to target-specific contrast agents for magnetic resonance imaging (MRI). MRI is a widely used technique in diagnostic medicine and biomedical research to obtain anatomical and physiological details of soft tissues. Contrast agents are used to enhance the contrast of MR images by causing changes to the chemical environment of water molecules. Clinically approved GdIII-containing contrast agents for MRI are non-specific, and consequently, have limited utility. Target-specific contrast agents represent one way to circumvent this limitation. In the research described in this thesis, myelin and Β-amyloid …

Modulation Of Water-Exchange Rates Of Lanthanide(Iii)-Containing Complexes Using Polyethylene Glycol, Buddhima Nirodhi Siriwardena-Mahanama

Wayne State University Dissertations

MODULATION OF WATER-EXCHANGE RATES OF LANTHANIDE(III)-CONTAINING COMPLEXES USING POLYETHYLENE GLYCOL

by

BUDDHIMA N. SIRIWARDENA-MAHANAMA

May 2014

Advisor: Dr. Matthew J. Allen

Major: Chemistry

Degree: Doctor of Philosophy

A modular system of lanthanide(III)-containing polyethylene glycol (PEG) conjugates was synthesized and characterized to investigate the influence of length and density of PEG on water-exchange rates of lanthanide(III)-containing complexes. The water-exchange rates of lanthanide(III)-containing complexes contribute to the efficiency of these complexes as T₁-shortening and paramagnetic chemical exchange saturation transfer (PARACEST) contrast agents for magnetic resonance imaging (MRI). Because the mechanism of these two MRI methods is vastly different, there is …

Studies On The Physicochemical Properties Of Eu2+ Cryptates: Implications To Contrast Agents For Magnetic Resonance Imaging, Joel Garcia

Wayne State University Dissertations

Magnetic resonance imaging (MRI) is a powerful medical imaging technique that can be enhanced using metal complexes called contrast agents. Most clinically approved contrast agents contain Gd³⁺. However, the efficiency (also known as relaxivity) of these Gd³⁺-containing complexes decreases as field strength increases, and in the ultra-high field strength regime, the relaxivity of these complexes is decreased considerably. Because of the slow water-exchange rate of most Gd³⁺-containing complexes (∼;10⁶ s^-1), I used Eu²⁺ instead of Gd³⁺ and adapted the ligand modification strategies that have been used for Gd^{3+ …}