Code: WOC	Time Slot/Poster Number: 10:45-11:10	Session: Hyperpolarization & Sensitivity Enhancements
Development of Hyperpolarized Krypton-83 Pulmonary Magnetic Resonance
Karl Stupic2; Nancy Elkins3; Galina Pavlovskaya1; John Repine3; Thomas Meersmann1, 2
1University of Nottingham, Nottingham, United Kingdom; 2Colorado State University, Fort Collins, Colorado; 3University of Colorado Health Sciences Center, Denver, Colorado
Abstract
The relaxation of krypton-83 is susceptible to the surface-to-volume ratio, surface hydration, and surface temperature in porous systems. Hyperpolarized krypton-83 with a 13,000 fold polarization enhancement at 9.4 T (6% spin polarization) was obtained through spin exchange optical pumping in a dilute 25% krypton gas mixture. The hp krypton-83 was inhaled into excised rat lungs for T1 relaxation measurements (spatially not resolved). Surprisingly, the relaxation in the alveolar space of ex vivo lungs is not a function of lung inflation despite the presumably changing surface to volume ratios in the alveoli. The first hp-83Kr FLASH image of in situ rat lungs at 9.4T was obtained. The relaxation of is slow enough to permit future in vivo studies.

Code: WOC	Time Slot/Poster Number: 11:10-11:25	Session: Hyperpolarization & Sensitivity Enhancements
Transfer of parahydrogen derived spin order at low magnetic field sensitizes NMR measurements by three orders of magnitude
Simon Duckett1; Kevin Atkinson1; Michael Cowley1; Ralph Adams1; David Kilgour3; Ryan Mewis1; David Williamson1; Richard Green1; Joost Lohman3; Gary Green2; Rainer Kerssebaum3
1Department of Chemistry, York, United Kingdom; 2York Neuroimaging Centre, York, UK; 3Bruker BioSpin, Rheinstetten, Germany
Abstract
A labile metal complex can facilitate the transfer of parahydrogen derived spin order to an organic substrate within a few seconds such that 15,000 fold increases in proton and carbon signal strengths are seen without chemical modification. These hyperpolarized signals are then employed in a range of 1 and 2 dimensional NMR procedures, in conjunction with a flow probe, to demonstrate that it is possible to rapidly characterise the substrate even at low concentrations. The efficiency of this process, and the nature of the magnetization created, depends on both the strength of the magnetic field where polarization transfer occurs and the lifetime of the interaction with parahydrogen.

Code: WOC	Time Slot/Poster Number: 11:25-11:50	Session: Hyperpolarization & Sensitivity Enhancements
Pre-Clinical Studies of Hyperpolarized Carbon-13 Metabolic Imaging
Daniel B Vigneron1; Peder Larson1; Ralph Hurd2; Sarah Nelson1; John Kurhanewicz1
1University of California, San Francisco, CA; 2GE Healthcare, Menlo Park, CA
Abstract
Hyperpolarized Carbon-13 MR is extraordinary new technique that has the potential to become an important new radiological tool for metabolic imaging by directly observing key cellular bioenergetic processes in vivo While many studies have focused on utilizing the >10,000 fold signal enhancement provided from this method for basic science studies, the focus of this research is to develop and translate hyperpolarized carbon-13 methods for future clinical trials. Recent work has focused on developing improved MR sequences and investigations of other agents and other applications including liver cancer and brain tumors.

Code: WOC	Time Slot/Poster Number: 11:50-12:05	Session: Hyperpolarization & Sensitivity Enhancements
Understanding the Diacetyl Hydration/Dehydration Mechanism to Optimize Singlet State Lifetimes
Yuming Chen; Taoyuan Feng; Elizabeth Jenista; Warren Warren
Chemistry Department, Duke University, Durham, NC
Abstract
Tremendous enthusiasm for hyperpolarization methods has recently emerged because of its ability to overcome the intrinsic sensitivity of MRI. However, the hyperpolarized signal is still greatly limited by T1 relaxation, restricting its application. A practical solution is to store this signal in the singlet state in a two-spin system, which is long-lived because it has no dipole moment to any other states and is therefore protected from T1 relaxation. Through the controlled interconversion between diacetyl and its monohydrate, equivalent spins can be used to produce and store excess population in this singlet state. This poster explores the dehydration and hydration dynamics of diacetyl, both in water and in water/cosolvent mixtures, in order to characterize the limit of this extension.