Iron-Based Contrast Agents as an alternative to Gadolinium-Based Contrast Agents for Magnetic Resonance Imaging (MRI)

The PhD project is dedicated to the development and comprehensive characterization of small molecular weight Fe(III)-based T1 contrast agents as safer and more sustainable alternatives to Gadolinium based agents (GBCAs). The study place a strong emphasis on the unique advantages of Fe(III), a naturally occurring bio-metal, particularly its favourable safety profile and potential for clinical translation in biomedical imaging. The first chapter introduces the basics of MRI technology and underscore the suitability of Fe(III) complexes for anatomical imaging. Current challenges and ongoing efforts to advance Fe(III) chelates toward clinical applications were also discussed. The second chapter focused on the synthesis and overall characterization of a novel Fe(III) complex. Key investigations include its biocompatibility and relaxivity performance, thus its potential as a high-efficiency MRI agent. The third chapter represents a collaborative project with the Indian Institute of Science, led by Professor Hussain, focused on the development of multifunctional Fe(III)-based theranostic probe. The investigated compound demonstrated notable progress in targeted cancer theranostics, incorporating four distinct functionality in a unique system: a glucose moiety to target tumor cancer cells, a photodynamic therapy feature, fluorescent component for optical imaging, and robust T1 MRI contrast properties. In the fourth chapter, the application of an Fe(III) complex is explored through the formulation of an injectable and biocompatible hydrogel designed for in vivo T1 weighted MRI tracking. The hydrogel, loaded with the well-performing Fe(DFX)2]3- complex, was widely characterized for its rheological properties, relaxometric behaviour and in vivo performance in healthy mice. The present study was carried out in collaboration with the University of Naples Federico II. Overall, the manuscript highlights the immense potential of Fe(III) complexes in next-generation MRI diagnostic and biomedical platform.