PHIP and MRI

MARÍA BELÉN FRANZONI

Workshop; Hot Topics in spin-hyperpolarization; 2012

The hydrogenation with parahydrogen (pH 2 ) is a promising technique to boost the low sensitivity in NMR experiments [1]. The Parahydrogen Induced Polarization (PHIP) technique involves a catalytic reaction in which hydrogen molecules enriched in the parastate are added to an unsaturated precursor. If the intrinsic symmetry of the pH 2 is broken in the product molecule, the resulting NMR spectrum intensities are strongly enhanced. In this talk, the main PHIP’s concepts are introduced. Then, a method which take advantage of the nature of the initial singlet state is introduced. Once the symmetry of the pH 2  state is broken, for example in high fields, the initial state and consequent evolution differs from the Boltzmann initial state. This difference promotes the use of PHIP technique as contrast agent for MRI, even in experiments where the observation of hyperpolarized signal is limited by the enormous amount of protons in the background [2].