A Simple Route to Strong Carbon-13 NMR Signals Detectable for Several Minutes.

ABSTRACT: Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) suffer from low sensitivity and limited nuclear spin memory lifetimes. Although hyperpolarization techniques increase sensitivity, there is also a desire to increase relaxation times to expand the range of applications addressable by these methods. Here, we demonstrate a route to create hyperpolarized magnetization in ¹³ C nuclear spin pairs that last much longer than normal lifetimes by storage in a singlet state. By combining molecular design and low-field storage with para-hydrogen derived hyperpolarization, we achieve more than three orders of signal amplification relative to equilibrium Zeeman polarization and an order of magnitude extension in state lifetime. These studies use a range of specifically synthesized pyridazine derivatives and dimethyl p-tolyl phenyl pyridazine is the most successful, achieving a lifetime of about 190?s in low-field, which leads to a ¹³ C-signal that is visible for 10 minutes.

SUBMITTER: Roy SS 

PROVIDER: S-EPMC5582603 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature