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Abstract Metabolic magnetic resonance imaging (MRI) using hyperpolarized (HP) pyruvate is becoming a non‐invasive technique for diagnosing, staging, and monitoring response to treatment in cancer and other diseases. The clinically established method for producing HP pyruvate, dissolution dynamic nuclear polarization, however, is rather complex and slow. Signal Amplification By Reversible Exchange (SABRE) is an ultra‐fast and low‐cost method based on fast chemical exchange. Here, for the first time, we demonstrate not only in vivo utility, but also metabolic MRI with SABRE. We present a novel routine to produce aqueous HP [1‐13C]pyruvate‐d3for injection in 6 minutes. The injected solution was sterile, non‐toxic, pH neutral and contained ≈30 mM [1‐13C]pyruvate‐d3polarized to ≈11 % (residual 250 mM methanol and 20 μM catalyst). It was obtained by rapid solvent evaporation and metal filtering, which we detail in this manuscript. This achievement makes HP pyruvate MRI available to a wide biomedical community for fast metabolic imaging of living organisms.
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This content will become publicly available on November 1, 2025
Signal Amplification by Reversible Exchange and its Translation to Hyperpolarized Magnetic Resonance Imaging in Biomedicine
Abstract Hyperpolarized magnetic resonance imaging (HP‐MRI) has emerged as a powerful tool in molecular imaging, providingin vivo, real‐time insights into metabolic pathways without ionizing radiation. Signal Amplification by Reversible Exchange (SABRE) represents a promising hyperpolarization technique, leveraging parahydrogen to enhance MRI signals. In this concept, we delineate the evolution of SABRE and landmark papers that have enabled us recently to produce biocompatible and low‐cost hyperpolarized pyruvate within minutes forin vivometabolic imaging, showcasing SABRE′s potential for preclinical and near‐future clinical settings. Looking ahead, with ongoing efforts focused on optimizing polarizer technology and expanding applications beyond pyruvate, we envision SABRE as a key player in the research and application of HP‐MRI due to its simplicity and throughput.
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- Award ID(s):
- 1904780
- PAR ID:
- 10607860
- Publisher / Repository:
- Wiley-VCH
- Date Published:
- Journal Name:
- Analysis & Sensing
- Volume:
- 4
- Issue:
- 6
- ISSN:
- 2629-2742
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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