%0 Journal Article %J The Journal of Physical Chemistry Letters %D 2018 %T Rapid Catalyst Capture Enables Metal-Free para-Hydrogen-Based Hyperpolarized Contrast Agents %A Danila A Barskiy %A Lucia A Ke %A Xingyang Li %A Vincent Stevenson %A Nevin Widarman %A Hao Zhang %A Ashley Truxal %A Alexander Pines %X

Hyperpolarization techniques based on the use of para-hydrogen provide orders of magnitude signal enhancement for magnetic resonance spectroscopy and imaging. The main drawback limiting widespread applicability of para-hydrogen-based techniques in biomedicine is the presence of organometallic compounds (the polarization transfer catalysts) in solution with hyperpolarized contrast agents. These catalysts are typically complexes of platinum-group metals, and their administration in vivo should be avoided. Herein, we show how extraction of a hyperpolarized compound from an organic phase to an aqueous phase combined with a rapid (less than 10 s) Ir-based catalyst capture by metal scavenging agents can produce pure para-hydrogen-based hyperpolarized contrast agents, as demonstrated by high-resolution nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The presented methodology enables fast and efficient means of producing pure hyperpolarized aqueous solutions for biomedical and other uses.

%B The Journal of Physical Chemistry Letters %V 9 %P 2721–2724 %8 05/2018 %G eng %U https://pubs.acs.org/doi/abs/10.1021/acs.jpclett.8b01007 %R 10.1021/acs.jpclett.8b01007