Transfer of Parahydrogen-Induced Polarization to 19F:
Bargon J, Rizi R, Bommerich U, Kuhn L
University of Bonn
Parahydrogen-Induced Polarization (PHIP) leads to strong signal enhancement in 1H-NMR if unsaturated substrates are hydrogenated with parahydrogen applying an appropriate catalyst. As has been shown before, this polarization can be transferred to heteronuclei such as 13C. For imaging the lung, a 19F-hyperpolarized contrast agent should be available, if possible for inhalation. Normally, this demands aerosols; however, fluorinated gases may also qualify. We have found that hyperpolarization of 19F characteristically depends on the distribution of the 19F and initially para protons in the hydrogenation product, rendering structural isomers suitable for the purpose to a different degree, due to different molecular shapes and associated dipolar couplings. Nonetheless, our preliminary findings suggest that in principle generating 19F-hyperpolarized contrast agents for inhalation to image the lung using 19F MRI is feasible.