Author/Authors :
Soikkeli, Maiju Department of Chemistry - University of Helsinki - Helsinki, Finland , Kettunen, Mikko I University of Eastern Finland - Kuopio, Finland , Nivajarvi, Riikka University of Eastern Finland - Kuopio, Finland , Olsson, Venla University of Eastern Finland - Kuopio, Finland , Ronkko, Seppo Department of Applied Physics - University of Eastern Finland - Kuopio, Finland , Laakkonen, Johanna P University of Eastern Finland - Kuopio, Finland , Lehto, Vesa-Pekka Department of Applied Physics - University of Eastern Finland - Kuopio, Finland , Kavakka, Jari Department of Chemistry - University of Helsinki - Helsinki, Finland , Heikkinen, Sami Department of Chemistry - University of Helsinki - Helsinki, Finland
Abstract :
Magnetic resonance imaging examinations are frequently carried out using contrast agents to improve the image quality.
Practically all clinically used contrast agents are based on paramagnetic metals and lack in selectivity and specificity. A group
of stable organic radicals, nitroxides, has raised interest as new metal-free contrast agents for MRI. Their structures can easily
be modified to incorporate difierent functionalities. In the present study, a stable nitroxide TEEPO (2,2,6,6-tetraethylpiperidin-1-oxyl) was linked to a glucose moiety (Glc) to construct a water-soluble, potentially tumor-targeting compound with
contrast-enhancing ability. The ability was assessed with in vivo MRI experiments. The constructed TEEPO-Glc agent proved
to shorten the T1 relaxation time in tumor, while the T1 time in healthy brain tissue remained the same. The results indicate the
potential of TEEPO-Glc as a valuable addition to the growing field of metal-free contrast enhancement in MRIbased diagnostics.
