10.1002/anie.201812759
Angewandte Chemie International Edition
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linewidth, relaxation time, and chemical shift, suggesting that Experimental Section
hyperpolarized NMR spectroscopy can be used for label-free real-
Detailed synthetic protocols and experimental methods along
with Figures S1-S16 and Table S1 are available in the Supporting
Information document.
time analysis of aspirin-protein binding interactions. This finding
is consistent with previous work showing the utility of
hyperpolarized 19F-NMR for the study of ligand-protein binding
interactions in the slow- and fast-exchange regimes.[21]
Acknowledgements
This work was supported by MD Anderson start-up funds (S.W.M.,
P.B.), R21CA181994 (S.W.M.), 2R44CA206771 (S.W.M.),
R21CA185536 (P.B.), CPRIT RP180164 (P.B.), CDMRP
PC110065 (N.Z., J.L., P.B.), Colleen’s Dream Foundation (NZ),
an MD Anderson Institutional Research Grant (N.Z., P.B.), and a
grant from the Gulf Coast Consortium (J.L., P.B.). Additional
funding was provided by a G.E. In-kind Multi-investigator Imaging
(MI2) Research Award (S.W.M, P.B.), the Boone Pickens
Distinguished Chair for Early Prevention of Cancer, The Duncan
Family Institute, the Colorectal Moon Shot, 1R01CA187238,
5R01CA1722670, and 1R01CA184843. A.O. was supported by a
cancer prevention educational award (R25T CA057730, Dr. Shine
Chang, PI). S.P. was supported by Gulf Coast Consortia/Keck
Center postdoctoral fellowship CPRIT RP170593. The MD
Anderson Nuclear Magnetic Resonance Facility and Small Animal
Imaging Facility (SAIF) are supported by the MD Anderson
Cancer Center Support Grant 5P30CA016672 (Dr. Peter Pisters).
We also thank the staff at the SAIF and the NMR facility for their
assistance with the magnetic resonance imaging experiments
and the Department of Scientific Publications at MD Anderson
Cancer Center for reading and editing this manuscript.
Figure 4. In vivo imaging and spectroscopy of hyperpolarized double-labeled
aspirin (2). a) Overlaid 1H and 13C (false color) coronal image immediately after
injection of hyperpolarized (2). The posterior of the mouse was placed inside
the volume coil. b) Same as a) except the anterior of the mouse occupies the
volume coil and imaging was initiated 5 seconds after injection. Single 13C
transient arrays following injection of hyperpolarized (2) with posterior c) or
anterior d) of the mouse placed in the volume coil. The resonance for (2) is
readily observed at 174.5 ppm for approximately 30 seconds when
spectroscopy is initiated immediately after injection (c).
Keywords: aspirin • hyperpolarization • magnetic resonance
imaging • magnetic resonance spectroscopy • chemopreventive
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