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Abstract Metronidazole and nimorazole are antibiotics of a nitroimidazole group which also may be potentially utilized as hypoxia radiosensitizers for the treatment of cancerous tumors. Hyperpolarization of15N nuclei in these compounds using SABRE‐SHEATH (Signal Amplification By Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei) approach provides dramatic enhancement of detection sensitivity of these analytes using magnetic resonance spectroscopy and imaging. Methanol‐d4is conventionally employed as a solvent in SABRE hyperpolarization process. Herein, we investigate SABRE‐SHEATH hyperpolarization of isotopically labeled [15N3]metronidazole and [15N3]nimorazole in nondeuterated methanol and ethanol solvents. Optimization of such hyperpolarization parameters as polarization transfer magnetic field, temperature, parahydrogen flow rate and pressure allowed us to obtain an average15N polarization of up to 7.2–7.4 % for both substrates. The highest15N polarizations were observed in methanol‐d4for [15N3]metronidazole and in ethanol for [15N3]nimorazole. At a clinically relevant magnetic field of 1.4 T the15N nuclei of these substrates possess long characteristic hyperpolarization lifetimes (T1) of ca. 1 to ca. 7 min. This study represents a major step toward SABRE in more biocompatible solvents, such as ethanol, and also paves the way for future utilization of these hyperpolarized nitroimidazoles as molecular contrast agents for MRI visualization of tumors.
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This content will become publicly available on April 22, 2026
Detection of 15 N-labeled metabolites in microbial extracts using AI-designed broadband pulses for 1 H, 15 N heteronuclear NMR spectroscopy
New AI-designed RF pulses increase bandwidth and sensitivity for1H-15N HSQC spectra of metabolites.
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- Award ID(s):
- 2304829
- PAR ID:
- 10614586
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- The Analyst
- Volume:
- 150
- Issue:
- 9
- ISSN:
- 0003-2654
- Page Range / eLocation ID:
- 1856 to 1861
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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