N.V. Anisimov –  Dr.Sc. (Phys.-Math.), Senior Research Scientist, Laboratory of a Magnetic Tomography  and Spectroscopy, Faculty of Fundamental Medicine, Lomonosov Moscow State University E-mail: anisimovnv@mail.ru

A.G. Agafonnikova –  Student, Department of Photonics and Physics of Microwaves, Faculty of Physical,  Lomonosov Moscow State University E-mail; agafon4ik96@yandex.ru

A.V. Kosenkov –  Student, Department of Biophysics, Faculty of Physical, the Lomonosov Moscow State University  E-mail: koss1741@yandex.ru

Yu.A. Pirogov –  Dr.Sc. (Phys.-Math.), Professor, Faculty of Physics, M.V. Lomonosov Moscow State University  National Research Nuclear University MEPhI, Engineering Physics Biomedical Institute E-mail: yupi937@gmail.com

The paper reports about 0.5 Tesla clinical scanner registration of NMR signals different from protons – 2H, 13C, 17O, 19F, et al. Application of polarization transfer from protons or fluorine-19 for enhancement of carbon 13C NMR signals is considered. Possibility of using the given scanner in multinuclear modes is noted not only in biomedical investigations but for technological applications as well. 

Methods of magnetic resonance – high resolution local NMR spectroscopy and magnetic resonance imaging (MRI) are widely used in the study of living objects, including humans. Generally, they register signals from protons (1H), since the hydrogen atoms are widely represented in living tissues, based on organic molecules and water. Registration of non-proton nuclei (13C, 15N, 17O, etc.), included to living tissues, may provide additional information on their status (possible pathologies) and biochemical processes. The problem of detecting these nuclei is sensitivity, due to their small gyromagnetic ratio γ, low natural content in nature, and for some of the isotopes, an almost total lack in living organs. Therefore, for the in vivo MRI method registration nuclei other than protons, it is often chosen the high (up to 100%) natural content nuclei presented sufficiently in studied organs, for example, 31P and 23Na. Registration of other heavy nuclei is problematic now even in strong fields. However, MRI use their as contrast agents in the study of respiratory organs (lung) and the study of metabolic processes. For this, drugs isotopes enriched and/or subjected to hyperpolarization are introduced to the body. The registration of fluorine-19 (19F) nuclei presents particular interest. This isotope with its 100% natural content has the gyromagnetic ratio γ just on 6% less than proton. Although fluorine is almost non-existent in living tissues, it is widely used in the manufacture of medicinal products. Fluorine-19 NMR and MRI techniques allow you to determine the localization of injected into the body drug and its evolution. High sensitivity of MRI with the nuclei of fluorine-19 is facilitated by the lack of background on the 19F MRI images from normal tissues, information about which is easy to get from a regular proton MRI. NMR techniques are applied not only in medicine and structural analysis of molecules, but also for technological purposes – in defectoscopy, food analyzing, industrial product identification, etc. In the case of non-invasive measurements, not only NMR spectrometers can be used, but clinical MRI scanners. This is especially true when the volume of the researched object is greater than 1 cm3 and it cannot be accommodated to the usual high resolution spectrometer. But during tomographic registrations, object sides can be commensurated with human dimensions, i.e. in hundreds times more than the working field of the spectrometer with signal amplification possibilities. The problem, however, is in that the typical clinical scanner usually not focused on multinuclear applications. This paper shows they can use such methods quite successfully.

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