Development of Hyperpolarized NMR Molecular Probes for Biological Applications

Our bodies are composed of molecules. The dynamic activity of molecules is the essence of living phenomena. Toward the analysis of this, the establishment of in vivo molecular imaging techniques has been sought. Hyperpolarized nuclear magnetic resonance (NMR) is a promising technique that enables in vivo molecular imaging using highly sensitive hyperpolarized NMR molecular probes and is expected to be a next-generation molecular imaging technology. However, a major challenge lies in the rapid relaxation of the hyperpolarized nuclear spin state of the molecule, i.e., a short lifetime of high sensitivity. We have made our efforts to address this critical issue. This award account mainly describes our research to develop hyperpolarized molecular probes with long hyperpolarization lifetime. Based on the understanding of the relaxation mechanism of hyperpolarized spin states, we successfully developed various hyperpolarized 13C molecular probes, some of which were applied for in vivo studies. In addition, we demonstrated the development of hyperpolarized 15N molecular probes with remarkably long hyperpolarization lifetimes. These results pave the way for the rational design of hyperpolarized molecular probes, which has been difficult to achieve so far. Hyperpolarized nuclear magnetic resonance is a promising technique for in vivo molecular imaging. Based on the understanding of the relaxation of hyperpolarized spin states, we developed various hyperpolarized molecular probes, some of which were applied for in vivo studies. These results pave the way for the rational design of hyperpolarized molecular probes, which has been difficult to achieve so far.