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Contrast agents for 19F magnetic resonance imaging
Dobrovolná, Tereza ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Complexes of transition metal ions with ligands containing fluorine atoms represent an interesting group of 19 F MRI contrast agents that could facilitate the diagnosis of various diseases. The presence of a paramagnetic metal ion in the vicinity of the 19 F nucleus results in shorter relaxation times and the possibility to obtain more NMR spectra in a given time, leading to better resolution. This work deals with the synthesis of the fluorinated macrocyclic ligand H3NOTPtfe , the preparation of its complexes with transition metal ions, their characterization and study by methods suitable for assessing their applicability in 19 F MRI, i.e. relaxometric NMR measurements and electrochemistry. The results show that the chosen concept is promising for 19 F MRI. The prepared complexes are applicable as 19 F MRI contrast agents, some even as redox active 19 F MRI "smart" contrast agents. The best properties were observed for the complex [Co(NOTPtfe )]− . Keywords: heteronuclear MRI, contrast agent, fluorine, PRE effect, spin relaxation, magnetic resonance imaging, paramagnetic complexes
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Macrocycles and complexation of large metal cations
Faltejsek, Jan ; Hermann, Petr (advisor) ; Drahoš, Bohuslav (referee)
In the last years, radioisotopes of heavy elements from the bottom of the Periodic Table have been increasingly used in nuclear medicine with focus on alpha-therapy. These large metal ions demand ligands fulfilling their special requirements. Complexes of polyazamacrocyclic ligands have been used in radiomedicine for a long time as diagnostic and therapeutic agents. This work aims to con- tribute to understanding of coordination chemistry of large macrocycles toward large metal ions. Thus, this work deals with structural studies, formation and decomplexation kinetics of Ln(III)-H4pyta complexes employing X-ray solid-state and solution NMR/UV-Vis spectroscopic data. The H4pyta is a 18-membered hexaazamacrocycle formed by two pyridine units and four amine groups which are modified with four acetate pendant arms. In the solid state, several isomeric complexes were structu- rally characterized. Large Ln(III) ions form decacoordinated species with two and two acetates on each side of the macrocyclic N6-plane. Small Ln(III) binds the ligand in a nonadentate fashion with one pendant non-coordinated. In the middle of lanthanide series, both isomers were characterized for several Ln(III) ions. Formation of the complexes takes place in a three-step mechanism with fast formation of an out-of-cage intermediate...
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Contrast agents for 19F magnetic resonance imaging
Martinisková, Marie ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
The aim of this Master Thesis is to synthesize and study new macrocyclic ligands containing fluorine atoms for use as potencial contrast agents in 19 F magnetic resonance imaging. New ligands were designed as analogues of ligands used in contrast agents already utilized in clinical practice - macrocyclic ligand for complexation of trivalent lanthanide ions based on DOTA skeleton and series of macrocyclic ligands for complexation of divalent nickel ion based on cyclam skeleton. All designed ligands were synthesized a characterized. The complexes [LnIII (dotptfe )]− were tested in vitro and in vivo to study 19 F NMR relaxation times enhancements.
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