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Code: PE	Time Slot/Poster Number: 070	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Coherent Transfer of Hyperpolarization Between Residues During Site Selective Photooxidation of Dipeptide Trp-Trp
Alexandra Yurkovskaya¹; Olga Morozova¹; Natalia Saprygina¹; Hans-Martin Vieth²
¹International Tomography Center, Novosibirsk, Russian Federation; ²Freie Universität Berlin, Berlin, Germany
Abstract
High selectivity of the reversible photooxidation of dipeptide HTrp-TrpOH results in hyperpolarization formation on the microsecond timescale at the C-terminal residue. By using a fast field-cycling device, which shuttles the whole NMR probe, the dependence of the NMR pattern on e time delay after laser pulse for a set of magnetic fields Bp in the range 0.1 mT – 7 T was exploited. At low magnetic fields when nuclei are strongly coupled, hyperpolarization is redistributed coherently among all protons of the primarily polarized C-terminal residue and is transferred even to protons of the N-terminal residue. A “long-lived spin state” that allows saving the non-equilibrium polarization over a time much longer than the longitudinal spin relaxation time T1 was found.

Code: PE	Time Slot/Poster Number: 071	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Solid State Nuclear Spin Qubit System with Easily-Accessible Bath Cooled with Dynamic Nuclear Polarization using Photoexcited Triplet Electrons
Kenichiro Tateishi¹; Makoto Negoro¹; Keisuke Yuki¹; Akinori Kagawa¹; Kazuyuki Takeda²; Masahiro Kitagawa¹
¹Graduate School of Engineering Science,Osaka Univ, Toyonaka, Japan; ²Graduate School of Science,Kyoto Univ, Kyoto, Japan
Abstract
Using a single crystal of naphthalene doubly-doped with 0.005 mol% pentacene and 0.3 mol% 2,3-difluoronaphthalene (which has two distinguishable 19F qubits), we have succeeded in observing hyper-polarized 19F NMR signals in 11.7 T with our magnetic field-cycling system. The proton polarization obtained with "Dynamic Nuclear Polarization using photoexcited triplet electrons" is transferred to 19F spins via heteronuclear dipolar interactions by passing through near zero field. In this system, 19F spins construct the qubit system and 1H spins behave as the bath system which has long T1. We confirmed experimentally that 19F spins could be hyperpolarized repeatedly by contact to the 'cool' bath after the 19F spins polarization decayed.

Code: PE	Time Slot/Poster Number: 072	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Solid-State Nitrogen-14 Nuclear Magnetic Resonance Enhanced by Dynamic Nuclear Polarization using a Gyrotron
Marc A. Caporini¹; Veronika Vitzthum¹; Paul R. Vasos¹; Fabien Aussenac²; Frank Engelke³; Melanie Rosay⁴; Werner E. Maas⁴; Geoffrey Bodenhausen^{1, 5}
¹Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; ²Bruker BioSpin, Wissembourg, France; ³Bruker Elektronik GmbH, Rheinstetten, Germany; ⁴Bruker BioSpin Corp., Billerica, MA; ⁵Ecole Normale Supérieure, Paris, France
Abstract
By combining indirect detection of 14N with dynamic nuclear polarization (DNP), the signal-to-noise ratio can be dramatically improved and the recovery delay between subsequent experiments can be shortened. MAS spectra of glassy samples of the amino acid proline doped with the stable bi-radical TOTAPOL at 110 K were obtained in a 400 MHz solid-state NMR spectrometer equipped with a gyrotron for microwave irradiation at 263 GHz. DNP enhancement factors on the order of ε ~ 40 were achieved. The recovery delays can be reduced from 60 s without radicals at 300 K to 6 s with radicals at 100 K. Thus, DNP allows one to reduce the acquisition times of 13C-detected 14N spectra from several days to a few hours.

Code: PE	Time Slot/Poster Number: 073	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Quantitative Analysis of Enzyme Catalyzed Reactions by Hyperpolarized NMR
Haifeng Zeng; Sean Bowen; Christian Hilty
Texas A&M University, College Station, TX
Abstract
DNP provides a means to overcome the sensitivity limits of NMR, enabling the application of NMR spectroscopy for measuring the progress of chemical reactions. Here, we present a framework for the quantitative description of hyperpolarized NMR experiments applied to the study of enzyme catalyzed reactions. Using a modiﬁed Michaelis Menten model, which accounts for spin relaxation in addition to the concentration changes due to the reaction, it becomes possible to determine exact kinetic rates, as well as to conclude on properties of the enzyme-substrate complex even in cases where this species is not directly observable.

Code: PE	Time Slot/Poster Number: 074	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Multiple Echoes in Dissolved Hyperpolarized 129Xe
Steven W. Morgan^{1, 2}; Emmanuel Baudin²; Gaspard Huber¹; Patrick Berthault¹; Geneviève Tastevin²; Pierre-Jean Nacher²; Hervé Desvaux¹
¹CEA, IRAMIS, SIS2M, LSDRM, Gif-sur-Yvette, France; ²Laboratoire Kastler Brossel, ENS; CNRS; UPMC, Paris, France
Abstract
We have performed multiple echo experiments in dissolved hyperpolarized 129Xe. Our motivations include testing the effects of longitudinal relaxation, determining the spatial profile of the magnetization in connection with multiple NMR-maser emissions, and testing the range of previous predictions. Our pulse sequence is similar to CRAZED, except that we use a weak gradient throughout the acquisition and include slice select gradients during the rf pulses. We use simulations to model the effect of diffusion on the echo amplitudes, and also discuss the transition towards the unstable regime resulting from very large magnetizations.

Code: PE	Time Slot/Poster Number: 075	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Stabilizing Unstable Nuclear Precession in Highly Magnetized Liquids
Steven Morgan^{1, 2}; Emmanuel Baudin¹; Geneviève Tastevin¹; Pierre-Jean Nacher¹
¹Laboratoire Kastler Brossel, ENS; CNRS; UPMC, Paris, France; ²CEA, IRAMIS, SIS2M, LSDRM, Gif-sur-Yvette, France
Abstract
In highly polarized liquids, the distant dipolar field (DDF) introduces a non-linear, non-local contribution to the NMR dynamics that may lead to spin turbulence and spatiotemporal chaotic behavior. Our experiments using hyperpolarized liquid 3He-4He typically give us dipolar fields of order 0.1-1 µT. By using a feedback scheme, we are able to control the effects of radiation damping on our samples. We also use XY4 sequences to stabilize the effects of magnetic field inhomogeneities, allowing us to observe an exponential growth in the signal amplitude defects, even for relatively small DDFs. By controlling these and other imperfections, time reversal of DDF effects will be used to probe the scales of developing unstable patterns through measurements of irreversible diffusion-induced attenuation.

Code: PE	Time Slot/Poster Number: 076	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Automated Parahydrogen Induced Polarizer Employing Low Field NMR Spectrometer and Tunable RF Circuit
Kevin W Waddell; Ken Wilkens; Sasidhar Tadanki; Eduard Chekmenev; Bibo Feng
Vanderbilt, Nashville, TN
Abstract
A fully automated PASADENA-based polarizer is presented for in-vivo metabolic imaging. The system operates at 12 mT and uses a homogeneous 51 cm electromagnet. RF pulses are delivered to a double-tuned 1H/13C circuit. Delivery and shuttling of substrates is pulse-programmed alongside MR events and a built-in receiver enables fast optimization of hyperpolarization parameters without the necessity of a high field spectrometer.

Code: PE	Time Slot/Poster Number: 077	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Control of the Diffusion Time-Scaling in Molecular Wheel Nanotubes as Detected by Continuous-Flow Hyperpolarized Xenon-129 NMR
Clifford R Bowers¹; Chi-Yuan Cheng²; Theocharis Stamatatos¹; George Christou¹
¹Chemistry Department, University of Florida, Gainesville, FL; ²University of California, Santa Barbara, CA
Abstract
Hyperpolarized NMR was employed in a comparative study of Xe diffusion and interactions within the nanochannels formed by two differently sized gallium molecular wheels. The two compounds were selected on the basis of the size of the central cavity relative to the diameter of the Xe atom. While the pore of the Ga18 wheel is just large enough to accommodate two xenon atoms side-by-side, transport in the channels formed by stacking of the smaller Ga10 wheel is expected to be single-file. Indeed, selective saturation-recovery NMR confirms single file diffusion in the Ga10 channels, while in the Ga18 system, the data is consistent with normal diffusion. Thus, a transition in the diffusion time-scaling was induced simply by reducing the wheel size.

Code: PE	Time Slot/Poster Number: 078	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Hyperpolarized Xenon Magnetic Resonance Imaging of Combustion Processes
J. Peter Mustonen¹; Hyun Doug Shin¹; Dominic Graziani¹; Xin Zhou^{1, 2}; Vikram S. Bajaj¹; Alexander Pines¹
¹LBNL and Univ. of California, Berkeley, Berkeley, CA; ²Wuhan Institute of Physics and Mathematics, Wuhan, P.R. China
Abstract
There is considerable interest in new methods to probe the chemistry and thermodynamics of enclosed combustion processes. This study exploits the sensitivity of the chemical shift of xenon-129 to temperature and pressure to visualize combustion, beginning with MRI of an open diffusion flame. Combustion MRI is challenging due to the high temperatures and fast dynamics involved. A modified chemical shift imaging pulse sequence with velocity and acceleration compensation was used to generate chemical shift images of xenon-129 during combustion with a homebuilt water-cooled probe. This method can be applied to smoldering combustion, and remotely-detected imaging of microscale combustion processes including flames in microfluidic channels, miniature turbines and rocket nozzles, which are of interest due to their relatively high power densities.

Code: PE	Time Slot/Poster Number: 079	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
DNP NMR in Determination of Trace Amounts of Metabolites
Debadeep Bhattacharyya
Oxford Instruments, Concord, MA
Abstract
DNP NMR has been extensively used for direct determination of low gamma heteronuclei (such as 13C, 15N, etc.) in the field of NMR Spectroscopy. In this study, we report determination of trace amounts of metabolites or metabolic tracers or biomarkers in a complex metabolic mixture by monitoring the respective 13C DNP NMR signals. Optimal microwave frequencies for each metabolite or metabolic tracer or biomarker are obtained.

Code: PE	Time Slot/Poster Number: 080	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Dynamic Nuclear Polarization Experiments at 263 GHz: Experimental Methods and Applications to Biological Solids
Melanie Rosay¹; Shane Pawsey¹; Ralph Weber¹; Richard Temkin²; Robert Griffin²; Werner Maas¹
¹Bruker BioSpin Corporation, Billerica, MA; ²Massachusetts Institute of Technology, Cambridge, MA
Abstract
The sensitivity of solid-sate NMR can be enhanced by Dynamic Nuclear Polarization (DNP) experiments which transfer the higher polarization of unpaired electrons to nuclear spins. This transfer is driven by microwave irradiation of electron spins. We have developed a DNP spectrometer for solids experiments at 263 GHz microwave frequency, 400 MHz 1H frequency, and have measured DNP signal enhancements of up to 80 at 100 K using TOTAPOL biradical. The microwaves are generated by a continuous-wave gyrotron, transmitted to the NMR probe via corrugated waveguide, and irradiated on to a 3.2 mm rotor for magic angle spinning DNP experiments. This contribution focuses on characterization of experimental and sample preparation parameters affecting the DNP efficiency and applications to biological solids.

Code: PE	Time Slot/Poster Number: 081	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Multi Field Dynamic Nuclear Polarization for Studying Macromolecular Aggregation
Sandra Garcia¹; Jeffrey H. Walton¹; Brandon D. Armstrong²; Anna Pavlova²; Songi Han²; Michael J. McCarthy¹; Ravinath Kausik²
¹University of California Davis, Davis, CA; ²UC Santa Barbara, Santa Barbara, CA
Abstract
Dynamic nuclear polarization (DNP) at 0.35 T and 0.04 T is utilized to study water dynamics of coacervate system. It is found that DNP is a useful tool to monitor the pH dependence of coacervation. The translational correlation time of water is greatly reduced upon coacervation. Results show that DNP at 0.04 T is able to probe water dynamics of coacervate systems with correlation times between 0.1 and 10 ns where as DNP at 0.35 T is better suited for motions with correlation times of 0.01- 0.5 ns.

Code: PE	Time Slot/Poster Number: 082	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Micro-storage of p-H2 for Hyperpolarization
Joel A Tang¹; Roman Fleysher²; Francesca Gruppi¹; Daniel K Sodickson²; James W Canary¹; Alexej Jerschow¹
¹New York University, New York, NY; ²Dept. of Radiology, NYU, Langone Medical Center, New York, NY
Abstract
Para-hydrogen has shown to enhance the sensitivity of NMR spectroscopy by more than a factor of 104. The lifetime of the hyperpolarized enhancements after a chemical reaction usually last only a few seconds therefore requiring fast transportation to the NMR spectrometer. Here we present an easy-to-use low pressure p-H2 apparatus and a novel way to provide a continuous supply of p-H2 for the hydrogenation reaction, thus extending the time of availability of hyperpolarized signals. The hydrogenation of methyl 2-acetamidoacrylate is used to explore our method and we found that an enhanced signal can be observed more than 70 seconds after the start of the reaction. Lengthening this lifetime would be highly beneficial for many applications including diffusion and MRI experiments.

Code: PE	Time Slot/Poster Number: 083	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Sensitivity enhancement of hyperpolarized 13C-pyruvate DNP by proton detection
Eduard Chekmenev; Kevin Waddell
Vanderbilt University Institute of Imaging Science, Nashville, TN
Abstract
The detection sensitivity of MR imaging of hyperpolarized 1-13C-pyruvate metabolism to hyperpolarized 1-13C-lactate can be potentially enhanced by up to 47 fold using proton detection of this 13C-polarized tracer. In vivo polarization transfer losses associated with T2 are expected to be minimal because J3(1H-13C) in lactate spin system is relatively large, 4.1 Hz, resulting in optimal t(RINEPT)=60 ms and t(refocus)=20 ms. This significant sensitivity enhancement will benefit many imaging and spectroscopy based techniques by decreasing the detection limit and/or improving spatial resolution. Moreover, it should considerably speed up translation of pyruvate/lactate hyperpolarized imaging to the clinical setting.

Code: PE	Time Slot/Poster Number: 084	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Indirect Detection of Enzymatic Processes by Hyperpolarized NMR: Temporal Information, Enhanced Spectral Resolution and Slow Spin Relaxation
Talia Harris; Patrick Giraudeau; Lucio Frydman
Weizmann Institute of Science, Rechovot, Israel
Abstract
The outstanding sensitivity arising from ex situ DNP has triggered high expectations concerning the in vivo monitoring of metabolism and disease. So far such gains have materialized for experiments focusing on low-g nuclei, whose relatively long T1s enables them to withstand the transfer from the cryogenic hyperpolarizer to the reacting centers of interest. This study demonstrates that, when suitably merged with spatially-encoded methods, also indirectly-detected 1H NMR spectroscopy can be exploited in time-resolved hyperpolarized analyses. The principles and opportunities opened by this approach are exemplified by Choline’s phosphorylation by Choline Kinase, and by Acetylcholine’s hydrolization by Acetylcholine Esterase.

Code: PE	Time Slot/Poster Number: 085	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
13C-Photo-CIDNP-Enhanced Heteronuclear Correlation NMR Spectroscopy: Perspectives on boosting NMR sensitivity in biological samples
Jung Ho Lee; Ashok Sekhar; Silvia Cavagnero
University of Wisconsin-Madison, Madison, Wisconsin
Abstract
Photochemically induced dynamic nuclear polarization (photo-CIDNP) combines laser irradiation and NMR to hyperpolarize NMR-active nuclei in liquids. Here, we report the development of novel 13C photo-CIDNP approaches for resonance enhancement in 1H-13C heteronuclear correlation spectroscopy. The light CPE-(13C-Photo-CIDNP-Enhanced)-SE-HSQC experiment yields 50-fold (for one of the side-chain carbons) and 20-fold (for the alpha carbon) higher S/N in tryptophan relative to the dark experiment. The light experiment also provides 7-fold (side-chain carbon) and 2.5-fold (alpha carbon) higher S/N relative to regular SE-HSQC, despite the fact that the latter sequence involves a full H-to-C-to-H transfer. The above results suggest that 13C-1H photo-CIDNP may be a valuable tool for the sensitivity enhancement of both side-chain and backbone 13C-1H pairs in polypeptides and proteins.

Code: PE	Time Slot/Poster Number: 086	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Characterization of Transient Species in Reactions Studied by DNP-NMR
Sean Bowen; Christian Hilty
Texas A&M University, College Station, TX
Abstract
DNP-NMR is a valuable tool for the study of chemical and biochemical reactions in real time because of its ability to operate with reasonable, physiologically relevant concentrations. However, transient species and products may be present at low concentrations. In order to gain insight into reaction mechanisms, these species must be characterized without compromising the time resolution of the experiment. Through the use of reporter molecules and selective correlation experiments, important information about these species may be obtained. Reporter molecules serve to indicate their involvement either directly or indirectly via a change of chemical shift. Selective correlation experiments allow for a single known chemical shift to be used to probe the structure of the remainder of the molecule.

Code: PE	Time Slot/Poster Number: 087	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
More Efficient “Dynamic Nuclear Polarization” for Biomolecular Solid-State NMR by Deuteration of Proteins
Umit Akbey; W. Trent Franks; Arne Linden; Sascha Lange; Barth Jan van Rossum; Hartmut Oschkinat
Leibniz-Institut für Molekulare Pharmakologie, Berlin, Germany
Abstract
More efficient dynamic nuclear polarization (DNP) for biological solid-state NMR applications is presented. A 13C CPMAS DNP enhancement of 118 is achieved for perdeuterated-SH3 with 80% exchangeable proton ratio, whereas only an enhancement of 27 is obtained for the fully protonated-SH3. The use of perdeuterated-SH3 results in an increase in the DNP enhancements up to a factor of 2 and 4.4 for 1H MAS and 13C CPMAS spectra compared to same type of experiments on full protonated-SH3. Moreover, by using direct 13C excitation on the perdeuterated sample, a larger DNP enhancement of 148 is obtained. We have used different proton content at the exchangeable sites of the protein to find the optimum proton concentration for the best DNP enhancement.

Code: PE	Time Slot/Poster Number: 088	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Using High-Power Tunable ‘On-Chip’ Grating-Narrowed LDAs to Study the Interplay of Wavelength Offset, Temperature, and Xe Density during Xe SEOP
Michael J. Barlow²; Neil A. Eschmann¹; Nicholas Whiting¹; Panayiotis Nikolaou¹; Boyd M. Goodson¹
¹Southern Illinois University Carbondale, Carbondale, IL; ²University of Nottingham, Nottingham, UK
Abstract
The xenon nuclear spin polarization (PXe) achieved via spin-exchange optical pumping is normally expected to decrease precipitously with increasingly high xenon densities ([Xe]). Recently, we observed an interdependence between [Xe] and cell temperature, allowing high PXe values at high [Xe] (e.g. ~55% & ~11% at 50 & 2000 torr Xe). In situ low-field NMR allows monitoring of Xe polarization dynamics to estimate spin-exchange / destruction parameters; comparisons of these results with predicted values imply that the interdependence originates from contributions from both the spin-exchange rate and PRb. Next-generation, high-power laser diode arrays (narrowed by ‘on-chip’ Bragg gratings, spectrally tunable independent of flux) allow these effects to be studied in the context of [Xe]-dependent changes to the Rb absorption/polarization characteristics.

Code: PE	Time Slot/Poster Number: 089	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Cesium/Xenon Spin-Exchange Optical Pumping Using High-Power Laser Diode Arrays at the Cs D1 & D2 Wavelengths
Nicholas Whiting¹; Panayiotis Nikolaou¹; Neil A. Eschmann¹; Michael J. Barlow²; Boyd M. Goodson¹
¹Southern Illinois University Carbondale, Carbondale, IL; ²University of Nottingham, Nottingham, UK
Abstract
Because of a number of expected benefits, it has been predicted that improved performance could be achieved by using cesium—rather than rubidium—for generating hyperpolarized 129Xe via spin-exchange optical pumping (SEOP). However, to date no clear-cut advantage to using Cs has been realized. One limitation has been the lack of high-power light sources capable of exciting the Cs absorption lines (like those that exist for Rb). The availability of two novel high-power (>40 W) laser diode arrays tuned to the Cs D1 and D2 lines now allows a more complete exploration of the parameter space for Cs/129Xe SEOP--as well as quantitative comparisons with Rb D1 129Xe SEOP--under conditions relevant for generation of hyperpolarized xenon for NMR/MRI applications.

Code: PE	Time Slot/Poster Number: 090	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Time Resolved CIDNP as Tool for Quantitative Analysis of Hyperfine Couplings in Elusive Radicals
Alexey Kiryutin¹; Konstantin Ivanov¹; Olga Morozova¹; Alexandra Yurkovskaya¹; Talea Köchling²; Hans-Martin Vieth²
¹International Tomography Center, Novosibirsk, Russian Federation; ²Freie Universitaet Berlin, Berlin, Germany
Abstract
Theoretical and experimental studies are presented showing the possibility of extracting hyperfine coupling constants (HFCCs) in radicals from their geminate CIDNP spectrum recorded at high magnetic field. It is checked experimentally for radicals with known HFCCs that the CIDNP intensities, Pi, in the geminate spectrum are proportional to the corresponding HFCCs, ai. A theoretical estimate is derived predicting that the relation Pi=C•ai is accurate for systems even with small values of Δg•βB as long as they have a large number of spins. Thus, time resolved CIDNP, because it selectively can measure the geminate polarization, is a unique tool for analyzing the spin density distribution in elusive radicals. Several examples of 1H, 13C and 15N HFCCs in biomolecules will be shown.

Code: PE	Time Slot/Poster Number: 091	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Understanding and Exploiting Lifetime Enhancement with Hyperpolarized Reagents
Elizabeth Jenista; Michael Jenista; Rosa Branca; Xin Chen; Warren Warren
Duke University, Durham, NC
Abstract
In order to extend the utility of hyperpolarized compounds, we have developed a technique which stores hyperpolarized population in the relaxation protected singlet state, allowing the hyperpolarized population to survive longer than T1.We will present in vitro demonstrations and numerical calculations for the diacetyl molecule (and other molecules) and discuss the potential hyperpolarized lifetime extension provided by storage in the singlet state. We will also present studies which demonstrate the sensitivity of this storage to the reaction speed between the equivalent and inequivalent molecules.

Code: PE	Time Slot/Poster Number: 092	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Hyperpolarized 89Y Complexes as pH Sensitive NMR Probes
Ashish Jindal¹; Matthew Merritt¹; Eul Hyun Suh¹; Craig Malloy¹; Dean Sherry^{1, 2}; Zoltan Kovacs¹
¹University of Texas Southwestern Medical Center, Dallas, TX; ²University of Texas at Dallas, Richardson, TX
Abstract
Hyperpolarization via the dynamic nuclear polarization method, followed by fast dissolution, provides tremendous gains in signal-to-noise in both NMR and MRI experiments, but a primary bottleneck in its application is the T1 decay of the magnetization in the liquid state. Due to its long T1, hyperpolarized 89Y makes an excellent candidate as an in vivo imaging agent. Here we report both the chemical shift and T1 dependence upon pH for two hyperpolarized 89Y complexes, clearly demonstrating how such complexes can be used as sensitive spectroscopy and imaging probes to measure pH. Sample preparation methods designed to optimize solid state polarization are also reported.

Code: PE	Time Slot/Poster Number: 093	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
High Proton Polarization at Room Temperature in p-terphenyl Crystal with Dynamic Nuclear Polarization using Photoexcited Triplet Electrons
Makoto Negoro¹; Kenichiro Tateishi¹; Akinori Kagawa¹; Masahiro Kitagawa¹; Kazuyuki Takeda²
¹Graduate School of Engineering Science, Osaka Univ, Toyonaka, Japan; ²Graduate School of Science, Kyoto University, Kyoto, Japan
Abstract
It was reported that the proton polarization of about 0.7 were attained at 105 K and in 0.3 T in a single crystal of 0.018 mol% pentacene dopednaphthalene by repeating dynamic nuclear polarization using photoexcitedtriplet electrons for 10 hours so far. In this work, adopting p-terphenyl as host material, we have succeeded inachieving proton polarization of order 0.1 in 600 seconds at roomtemperature and in 0.4 T. We have confirmed that partial deuteration leadsto higher polarization more efficiently. This work allows new possibilities to get high sensitive NMR spectra withoutcooling as well as further developments in particular fields which requirehyperpolarization such as quantum computing and polarized target.

Code: PE	Time Slot/Poster Number: 094	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Para-hydrogenated Glucose Derivatives as Potential MRI 13C-hyperpolarized probes
Luisa Poggi
, Colleretto Giacosa (To), Italy
Abstract
A set of molecules in which a glucose moiety is bound to an hydrogenable synthon has been synthesized and evaluated for hydrogenation reactions and for the corresponding PHIP effects, in order to select suitable candidates for an “in vivo” MRI method for the assessment of glucose cellular uptake.

Code: PE	Time Slot/Poster Number: 096	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Studies of 129Xe to 1H Spin Polarization Transfer in Aqueous Xenon-Binding Systems
Ping He¹; Laura L. Walkup¹; Nicholas Whiting¹; Panayiotis Nikolaou ¹; Kathleen E. Chaffee²; Xiaoxia Li³; Boyd M. Goodson¹
¹Southern Illinois University, Carbondale, IL; ²Washington University, St. Louis, MO; ³Mississippi University for Women, Columbus, MS
Abstract
Although the resulting enhancements are typically small, it has previously been demonstrated that magnetization transfer from laser-polarized xenon to other solution spins (e.g., via the spin-polarization induced nuclear Overhauser effect, or SPINOE) can be structurally and dynamically informative. Despite the attraction for studying xenon-binding aqueous systems with such approaches, aqueous systems pose a number of additional and inherent challenges. We will present our initial efforts to study 129Xe to 1H polarization transfer in prototypical aqueous xenon-binding systems in the context of these challenges, including observations of selective enhancements in water soluble organic cage molecules.

Code: PE	Time Slot/Poster Number: 097	Session: Hyperpolarization & Ultra-Sensitive Detection Methods, Poster
Optimization of Hyperpolarized NMR Signals in Y-DOTA
Lloyd Lumata; Matthew Merritt; A. Dean Sherry; Craig Malloy; Zoltan Kovacs; Ashish Jindal
University of Texas Southwestern Medical Center, Dallas, TX
Abstract
In pursuit of achieving higher NMR signal-to-noise ratio for 89Y imaging, we have investigated dynamic nuclear polarization (DNP) of Y-DOTA complex in different glassing agents and measured the room-temperature 89Y NMR signal enhancement after dissolution. So far we have achieved a room-temperature 89Y NMR enhancement of ~15,000X, a significant improvement from 1,100X 89Y NMR enhancement reported from a previous study. These results will be discussed in light of the Borghini model and thermal mixing theory of DNP.