Hiroshi Hirata, Ph.D.

Professor, Principal Investigator (Electron Paramagnetic Resonance Spectroscopy and Imaging)

Mailing Address

Division of Bioengineering and Bioinformatics
Graduate School of Information Science and Technology
Hokkaido University
North 14, West 9, Kita-ku
Sapporo 060-0814

Office M-207
Phone & Fax +81-11-706-6762 (from abroad), 011-706-6762 (domestic phone call)
E-mail: hhirata *at* ist *dot* hokudai *dot* ac *dot* jp


Professional Career/Appointments

  • Professor, Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, since 2008.
  • Professor, Department of Electrical Engineering, Yamagata University, 2007-2008.
  • Visiting Professor, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland, 2015
  • Visiting Scholar, Davis Heart and Lung Research Institute, Ohio State University, Columbus, Ohio, USA, 2006.
  • Adjunct Assistant Professor of Radiology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA, 2000-2016.
  • Research Associate, Department of Radiology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA, 1999-2000.
  • Associate Professor, Department of Electrical Engineering, Yamagata University, 1996-2007.
  • Research Associate, Department of Electrical and Computer Engineering, Yamagata University, 1993-1996.
  • Vice President (Asia), International EPR (ESR) Society, 2018-2020.
  • Member, Exective Committee, International Society on Oxygen Transport to Tissue, 2018-2021.

Honors and Recognitions

  • Distinguished Reviewer, Magnetic Resonace in Medicine, International Society for Magnetic Resonance in Medicine (ISMRM), 2018.
  • Young Investigator Award, The Society of Electron Spin Science and Technology, 2003.

Administrative Appointments

  • Member, Board of Trustees, Yamagata University Research Institute Foundation, 2003-2008.
  • Director, Yamagata University Research Network System (YURNS, a virtual laboratory in Yamagata University), 2002-2007.
  • Grant Program Officer, Research Promotion Bureau, Ministry of Education, Culture, Sports, Science and Technology, Japanese Government, 2003-2005.

Research interests

Hiroshi Hirata has led the research team of electron paramagnetic resonance (EPR) spectroscopy and imaging in the Division of Bioengineering and Bioinformatics.

As an engineering scientist, Dr. Hirata has built the research program of instrumental development of EPR spectroscopy and imaging for biomedical applications. EPR spectroscopy is one of the magnetic resonance techniques, and it allows us to detect unpaired electrons in a subject non-invasively. EPR methods are applicable to small animals to investigate biological and medical problems.

The long-term goal of his research career is to establish advanced technologies in EPR spectroscopy and imaging to detect and visualize free radicals in animal disease models and even in a clinical setting.

Since his background is electrical engineering, his major competence is instrument development for EPR spectroscopy and imaging, especially for biomedical applications. To date, he has developed low-field continuous-wave (cw) EPR spectrometers that operate at 300 MHz, 750 MHz, and 1.1 GHz. His research team has developed not only cw-EPR spectrometers but also a 750-MHz cw-EPR imager. These EPR instruments have been intended for use in small rodents such as mice or rats.

Applications with significant impact drive instrument development in EPR techniques. EPR spectroscopy and imaging have unique capabilities to detect specific molecules with unpaired electrons. Chemical species called free radicals play major roles in biological processes. Among several biomedical subjects, Dr. Hirata is interested in EPR imaging of cancer tumors. Understanding of cancer tumors is very important for human life. If his research programs can bring new insights into cancer studies, the resulting biomedical technologies may contribute to improvements in clinical treatments and biomedical sciences.

With regard to instrument development in in vivo EPR spectroscopy, four practical considerations are strategically important: (1) sensitivity, (2) stability, (3) ease of operation, and (4) applications with significant impact. If his research can solve the technical difficulties mentioned above, it should have tremendous impact on the biomedical application of EPR techniques. In addition to the practical considerations of EPR spectroscopy, there are four key technical issues in EPR imaging: (1) resolution, (2) acquisition time, (3) mapping on anatomical images (multi-modal imaging), and (4) functional imaging (for example, pO2, pH, and redox status).

Dr. Hirata is a member of

He reviewed manuscripts for the following journals:

  • Journal of Magnetic Resonance
  • Magnetic Resonance in Medicine
  • NMR in Biomedicine
  • Review of Scientific Instruments
  • Applied Magnetic Resonance
  • Magnetic Resonance Imaging
  • Magnetic Resonance in Chemistry
  • Concepts in Magnetic Resonance Part B Magnetic Resonance Engineering
  • Radiotherapy and Oncology
  • Journal of Physical Chemistry
  • Journal of Physical Chemistry Letters
  • Medical Physics
  • Health Physics
  • IEEE Journal of Biomedical and Health Informatics
  • IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control

Also, he served as a reviewer for

Recent publications

  1. A. Taguchi, S. DeVience, B. Driesschaert, V. V. Khramtsov, and H. Hirata. In vitro simultaneous mapping of the partial pressure of oxygen, pH and inorganic phosphate using electron paramagnetic resonance. Analyst (2020). doi: 10.1039/D0AN00168F, published online 26 February 2020. https://doi.org/10.1039/D0AN00168F
  2. R. Nakaoka and H. Hirata, Noise characteristics of a 750-MHz electronically tunable resonator for electron paramagnetic resonance spectroscopy, AIP Advances, Vol. 9, No. 7, article no. 075312 (2019) (7 pages). doi: 10.1063/1.5099381, published online 18 July 2019. https://doi.org/10.1063/1.5099381 (Open Access)
  3. T. Yokoyama, A. Taguchi, H. Kubota, N. J. Stewart, S. Matsumoto, I. A. Kirilyuk, and H. Hirata, Simultaneous T2* mapping of 14N- and 15N-labeled dicarboxy-PROXYLs using CW-EPR-based single-point imaging, Journal of Magnetic Resonance, Vol. 305, pp. 122-130 (2019). DOI: 10.1016/j.jmr.2019.06.012, published online 26 June 2019. http://doi.org/10.1016/j.jmr.2019.06.012
  4. D. A. Komarov, Y. Ichikawa, K. Yamamoto, N. J. Stewart, S. Matsumoto, H. Yasui, I. A. Kirilyuk, V. V. Khramtsov, O. Inanami, and H. Hirata. In vivo extracellular pH mapping of tumors using electron paramagnetic resonance. Analytical Chemistry, Vol. 90, No. 23, pp. 13938-13945 (2018). DOI: 10.1021/acs.analchem.8b03328, published online 29 October 2018. [Selected as Supplementary Journal Cover] http://doi.org/10.1021/acs.analchem.8b03328
  5. R. Nakaoka, D. A. Komarov, S. Matsumoto, and H. Hirata. Impact of the characteristic impedance of coaxial lines on the sensitivity of a 750-MHz electronically tunable EPR resonator. Applied Magnetic Resonance, Vol. 49, No. 8, pp. 853-867 (2018). DOI: 10.1007/s00723-018-1001-6, published online 31 March 2018. http://doi.org/10.1007/s00723-018-1001-6
  6. H. Sato-Akaba, M. C. Emoto, H. Hirata, and H. G. Fujii, Design and testing of a 750 MHz CW-EPR digital console for small animal imaging, Journal of Magnetic Resonance, Vol. 284, pp. 48-58 (2017). DOI: 10.1016/j.jmr.2017.09.008, published online 20 September 2017. http://dx.doi.org/10.1016/j.jmr.2017.09.008
  7. T. Amida, R. Nakaoka, D. A. Komarov, K. Yamamoto, O. Inanami, S. Matsumoto, and H. Hirata, A 750-MHz electronically tunable resonator using microstrip line couplers for electron paramagnetic resonance imaging of a mouse tumor-bearing leg, IEEE Transactions on Biomedical Engineering, Vol. 65, No. 5, pp. 1124-1132 (2018). DOI: 10.1109/TBME.2017.2743232, published online 23 August 2017. http://dx.doi.org/10.1109/TBME.2017.2743232
  8. M. Umakoshi, I. Yamaguchi, H. Hirata, N. Kunugita, B. B. Williams, H. M. Swartz, M. Miyake, In vivo electron paramagnetic resonance tooth dosimetry: Dependence of radiation-induced signal amplitude on the enamel thickness and surface area of ex vivo human teeth, Health Physics, Vol. 113, No. 4, pp. 262-270 (2017). DOI: 10.1097/HP.0000000000000698, published online 7 August 2017. http://dx.doi.org/10.1097/HP.0000000000000698
  9. D. A. Komarov and H. Hirata, Fast backprojection-based reconstruction of spectral-spatial EPR images from projections with the constant sweep of a magnetic field, Journal of Magnetic Resonance, Vol. 281, pp. 44-50 (2017), DOI: 10.1016/j.jmr.2017.05.005, published online 17 May 2017. http://dx.doi.org/10.1016/j.jmr.2017.05.005
  10. H. Kubota, D. A. Komarov, H. Yasui, S. Matsumoto, O. Inanami, I. A. Kirilyuk, V. V. Khramtsov, and H. Hirata, Feasibility of in vivo three-dimensional T2* mapping using dicarboxy-PROXYL and CW-EPR-based single-point imaging, Magnetic Resonance Materials in Physics, Biology and Medicine, Vol. 30, No. 3, pp. 291-298 (2017). DOI: 10.1007/s10334-016-0606-8, published online 6 January 2017. http://dx.doi.org/10.1007/s10334-016-0606-8

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