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Abstract We report dissolution Dynamic Nuclear Polarization (d‐DNP) of [15N3]metronidazole ([15N3]MNZ) for the first time. Metronidazole is a clinically approved antibiotic, which can be potentially employed as a hypoxia‐sensing molecular probe using15N hyperpolarized (HP) nucleus. The DNP process is very efficient for [15N3]MNZ with an exponential build‐up constant of 13.8 min using trityl radical. After dissolution and sample transfer to a nearby 4.7 T Magnetic Resonance Imaging scanner, HP [15N3]MNZ lasted remarkably long with T1values up to 343 s and15N polarizations up to 6.4 %. A time series of HP [15N3]MNZ images was acquired in vitro using a steady state free precession sequence on the15NO2peak. The signal lasted over 13 min with notably long T2of 20.5 s. HP [15N3]MNZ was injected in the tail vein of a healthy rat, and dynamic spectroscopy was performed over the rat brain. The in vivo HP15N signals persisted over 70 s, demonstrating an unprecedented opportunity for in vivo studies.
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This content will become publicly available on February 6, 2026
15 N SABRE-SHEATH and NMR/DFT Characterization of Amino-Metronidazole, a Metabolic Product of the Antibiotic and Prospective Hypoxia Contrast Agent Metronidazole
- Award ID(s):
- 2404387
- PAR ID:
- 10600385
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry B
- Volume:
- 129
- Issue:
- 5
- ISSN:
- 1520-6106
- Page Range / eLocation ID:
- 1662 to 1669
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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