Department of Chemistry, Graduate School of Science
Nuclear medicine uses radioactive metal ions to treat and diagnose cancer. In such treatments and diagnoses, radiopharmaceuticals are used in which cancer-selective molecules such as antibodies are linked to radioactive metal ions with ligands in order to accumulate radioactive metal ions at target sites such as cancer cells.
Currently, 90Y, 177Lu, etc. are used as radioactive metal ions for treatment. In addition, Gd is not only used as a contrast agent in MRI, but among the stable isotopes of Gd, 157Gd has very large thermal neutron absorption cross section, and the gamma rays and Auger electrons generated in the neutron capture reaction are used for treatment. Thus, 157Gd is expected to be used in "theranostics" in which treatment and diagnosis are performed at the same time. Dota is currently widely used as a ligand to chelate these metal ions. While dota forms extremely stable complexes with these metal ions, complexation is slow and requires heating to complete the reaction, and this limits the use of heat-sensitive antibodies.
Therefore, I am aiming to synthesize chelate ligands that easily form complexes with yttrium and the latter half of the lanthanide series at room temperature and have higher stability for use in nuclear medicine.