caa a22 4500 605545324 CHVBK 20210128100935.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s00723-015-0671-6 doi (NATIONALLICENCE)springer-10.1007/s00723-015-0671-6 Passive Decoupling Due to Low Q -Factors of Four-Channel Coils in 300-MHz Pulsed EPR Imaging [Elektronische Daten] [Ayano Enomoto, Keita Saito, Sankaran Subramanian, Murali Krishna, Hiroshi Hirata, Nallathamby Devasahayam] This article describes a four-channel coil array for in vivo time-domain electron paramagnetic resonance (EPR) imaging applications. Decoupling of the individual element coils was achieved with the low-quality factors required in pulsed EPR at radiofrequency to accommodate the imaging bandwidth. No active decoupling method was used in the coil array. Remote control of a coaxial switch connected to the four-channel coil array was performed with voltage signals from a personal computer. To verify the operation of this four-channel coil array, a phantom tube filled with a solution of paramagnetic triarylmethyl radicals (OX063) was visualized by pulsed EPR imaging based on the single-point method involving pure phase encoding. In an in vivo experiment, OX063 in a mouse tumor-bearing right hind leg was visualized by pulsed EPR imaging. Even without active decoupling circuits, there was no shift in resonances for individual coils when those were tuned to the same frequency due to low quality factors and low coupling coefficients with neighboring coils. The coil assembly allowed us to study an object that was larger than an individual coil element, enabling the imaging of larger subjects with reduced overall specific absorption rate. Such strategies should be useful for studying larger objects by EPR imaging. Springer-Verlag Wien, 2015 Enomoto Ayano Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, North 14, West 9, Kita-ku, 060-0814, Sapporo, Japan aut Saito Keita Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut Subramanian Sankaran Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut Krishna Murali Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut Hirata Hiroshi Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, North 14, West 9, Kita-ku, 060-0814, Sapporo, Japan aut Devasahayam Nallathamby Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut Applied Magnetic Resonance Springer Vienna 46/6(2015-06-01), 671-683 0937-9347 46:6<671 2015 46 723 https://doi.org/10.1007/s00723-015-0671-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00723-015-0671-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Enomoto Ayano Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, North 14, West 9, Kita-ku, 060-0814, Sapporo, Japan aut NATIONALLICENCE 700 1- Saito Keita Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut NATIONALLICENCE 700 1- Subramanian Sankaran Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut NATIONALLICENCE 700 1- Krishna Murali Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut NATIONALLICENCE 700 1- Hirata Hiroshi Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, North 14, West 9, Kita-ku, 060-0814, Sapporo, Japan aut NATIONALLICENCE 700 1- Devasahayam Nallathamby Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 20892-1002, Bethesda, MD, USA aut NATIONALLICENCE 773 0- Applied Magnetic Resonance Springer Vienna 46/6(2015-06-01), 671-683 0937-9347 46:6<671 2015 46 723