CHAPTER 9. Hyperpolarization: Concepts, Techniques and Applications

Thermal annihilation of photo-induced radicals following dynamic nuclear polarization to produce transportable frozen hyperpolarized 13C-substrates

“…MRI can provide direct biochemical information via the spectroscopic dimension of nuclear magnetic resonance (NMR), allowing simultaneous acquisition of signals from a substrate and its metabolic products, hence yielding true metabolic imaging. The relatively low sensitivity of NMR can be circumvented using hyperpolarization techniques such as spin-exchange optical pumping for gases, and dissolution dynamic nuclear polarization (DNP), parahydrogen-induced polarization, as well as the so-called ‘brute force' method for liquids 4 5 6 . In the context of metabolic imaging, 13 C is the most adapted nucleus because of its ubiquitous presence in the vast majority of biomolecules, its large chemical shift dispersion allowing to easily differentiate the various species, its low natural abundance and its relatively long longitudinal relaxation time at specific molecular positions such as in a carboxyl group 1 7 8 9 10 11 .…”

Hyperpolarized Magnetic Resonance as a Sensitive Detector of Metabolic Function

“…Three schemes have so far been developed to provide hyperpolarized (HP) 13 C metabolic precursors dissolved in room-temperature aqueous solutions: the brute force method, parahydrogen-induced polarization (PHIP), and a method based on dynamic nuclear polarization (DNP), now commonly called dissolution DNP. The latter is currently the most versatile and established method, and we herein propose to review the field of dissolution DNP from physical and biological perspectives (a comparison of the three techniques can be found in ref ( 10 )). The dissolution DNP technique has recently reached a point at which it is ready to move from proof-of-principle studies toward applications aimed at solving specific biological and medical problems.…”