Multi-nuclear magnetic resonance spectroscopy: state of the art and future directions

Abstract

With the development of heteronuclear fluorine, sodium, phosphorus, and other probes and imaging technologies as well as the optimization of magnetic resonance imaging (MRI) equipment and sequences, multi-nuclear magnetic resonance (multi-NMR) has enabled localize molecular activities in vivo that are central to a variety of diseases, including cardiovascular disease, neurodegenerative pathologies, metabolic diseases, kidney, and tumor, to shift from the traditional morphological imaging to the molecular imaging, precision diagnosis, and treatment mode. However, due to the low natural abundance and low gyromagnetic ratios, the clinical application of multi-NMR has been hampered. Several techniques have been developed to amplify the NMR sensitivity such as the dynamic nuclear polarization, spin-exchange optical pumping, and brute-force polarization. Meanwhile, a wide range of nuclei can be hyperpolarized, such as 2H, 3He, 13C, 15 N, 31P, and 129Xe. The signal can be increased and allows real-time observation of biological perfusion, metabolite transport, and metabolic reactions in vivo, overcoming the disadvantages of conventional magnetic resonance of low sensitivity. HP-NMR imaging of different nuclear substrates provides a unique opportunity and invention to map the metabolic changes in various organs without invasive procedures. This review aims to focus on the recent applications of multi-NMR technology not only in a range of preliminary animal experiments but also in various disease spectrum in human. Furthermore, we will discuss the future challenges and opportunities of this multi-NMR from a clinical perspective, in the hope of truly bridging the gap between cutting-edge molecular biology and clinical applications.

Multinuclear MRI in Drug Discovery

“…In this technique, circularly polarized light is used to selectively optically pump (usually) rubidium (Rb) electrons, generating a highly spin-polarized Rb gas. A wide range of nuclei 2 H, 3 He, 13 C, 15 N, 31 P, and 129 Xe can be polarized [ 50 ]. The 129 Xe hyperpolarization method can be used for lung imaging amongst others [ 51 ].…”

Considerations for hyperpolarized 13C MR at reduced field: Comparing 1.5T versus 3T

“…Hyperpolarized $$$ {}^{13} $$$C MRI and MR spectroscopy (MRS) are used for monitoring real‐time metabolism in vivo 1‐3 …”

“…Hyperpolarized 13 C MRI and MR spectroscopy (MRS) are used for monitoring real-time metabolism in vivo. [1][2][3] Typically, in vivo hyperpolarized 13 C MRI / MRS are performed at field strengths ≥3T. Especially clinical examinations and preclinical studies in large animals are usually conducted at 3T 1 due to commercially available hardware suitable for the respective subject sizes with the capability of detecting non-1 H nuclei.…”

Multibranched-Based Fluorinated Materials: Tailor-Made Design of 19F-MRI Probes

“…Moreover, the urgent need to localize complex molecular activities in vivo , as well as track and quantify targets of biological interest (i.e., drugs, nanoparticles, etc. ), determined the fast development of heteronuclear fluorine, sodium, phosphorus, and other tracers and imaging technologies …”

“…), determined the fast development of heteronuclear fluorine, sodium, phosphorus, and other tracers and imaging technologies. 2 The 19 F nucleus with its 100% natural abundance, high gyromagnetic ratio (40.06 MHz/T), wide range of chemical shift (<350 ppm), and 83% sensitivity of 1 H is considered one of the most promising imaging nuclei. Thus, 19 F-MRI emerged as an extremely powerful quantification and tracking technique providing complementary information to 1 H-MRI.…”