Transition Metal Doping Reveals Link between Electron $T_{\mathrm{1}}$ Reduction and $^{\mathrm{13}}$C Dynamic Nuclear Polarization Efficiency

ORAL

Abstract

Since its invention in 2003, dissolution dynamic nuclear polarization (DNP) has been widely used to increase the weak signal strength of nuclear magnetic resonance (NMR). In this method, polarization is transferred from free electrons to nuclei using microwave irradiation at intermediate magnetic field and cryogenic temperatures and then rapidly dissolved using a superheated solvent. This process requires a source of free radicals, one of the most common being trityl OX063. At low field (3.35 T), polarization using trityl as the polarizing agent can be significantly enhanced by the addition of paramagnetic agents. In order to come to a greater understanding of this process, paramagnetic transition metal ion complexes were used as dopants for $^{\mathrm{13}}$C DNP using trityl. Mn$^{\mathrm{2+}}$-NOTA proved to be beneficial to polarization, while Co$^{\mathrm{2+}}$-NOTA and Cu$^{\mathrm{2+}}$-NOTA had no impact. Electron paramagnetic resonance studies showed that the $T_{\mathrm{1}}$ of trityl was shortened drastically by the manganese additive but remained unchanged with the addition of copper or cobalt. These results confirm the commonly assumed link between electronic $T_{\mathrm{1}}$ and DNP efficiency.

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Authors

  • Peter Niedbalski

    The University of Texas at Dallas, Univ of Texas, Dallas, University of Texas at Dallas

  • Christopher Parish

    University of Texas at Dallas, The University of Texas at Dallas

  • Qiye Zheng

    Santa Fe Institute, Baylor University, University of Texas at Dallas, Department of Chemistry, The University of Texas at Austin, Jozef Stefan Institute, Texas A&M University-Commerce, Commerce, Texas 75429, Cyclotron Institute, Texas A&M University, College Station, Texas 77843, Texas A&M University, Department of Physics, Texas State University, Department of Physics, Baylor University, University of Texas at El Paso, Univ of Texas, El Paso, University of Science and Technology of China, The University of Texas at Dallas, Faculty, None, Southwestern University, Texas State University, Texas A&M University - Commerce, UT Southwestern Medical Center, National High Magnetic Field Laboratory, The Cyclotron Institute at Texas A&M University, Department of Biological Sciences, Texas State Univ-San Marcos, The University of Texas at Dallas, Richardson, Texas 75080, King Abdullah University of Science and Technology, Univ of Texas, Dallas, N.Chiao Tung U., UT Dallas, Inorganic Chemistry and Catalysis Group, Utrecht University, Electrical & Computer Engineering, Baylor University, Department of Materials Science and NanoEngineering, Rice University, University of Texas at Arlington, University of Chicago, The University of Mississippi, Astronomical Observatory, Warsaw University, Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, Rochester Institute of Technology, California Institute of Technology, University of Houston, NASA-GSFC and UMBC, MD, Virginia Tech, VA, Texas Christian University, The University of Texas at San Antonio, Department of Physics, Teivecca Nazarene University, Weatherford College, Air Force Research Laboratory, Sensors Directorate, WPAFB, OH, USA, Air Force Research Laboratory, Directed Energy Directorate, KAFB, NM, US, Department of Physics & Astronomy, University of Texas at San Antonio TX, USA, University of Arizona, University of North Carolina at Chapel Hill, Stanford University, Harvard Center for Astrophysics, Texas A\&M University, UTSW, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, Boston College, Chestnut Hill, Massachusetts 02467, Naval Research Laboratory, Washington, D.C. 20375

  • Qiye Zheng

    Santa Fe Institute, Baylor University, University of Texas at Dallas, Department of Chemistry, The University of Texas at Austin, Jozef Stefan Institute, Texas A&M University-Commerce, Commerce, Texas 75429, Cyclotron Institute, Texas A&M University, College Station, Texas 77843, Texas A&M University, Department of Physics, Texas State University, Department of Physics, Baylor University, University of Texas at El Paso, Univ of Texas, El Paso, University of Science and Technology of China, The University of Texas at Dallas, Faculty, None, Southwestern University, Texas State University, Texas A&M University - Commerce, UT Southwestern Medical Center, National High Magnetic Field Laboratory, The Cyclotron Institute at Texas A&M University, Department of Biological Sciences, Texas State Univ-San Marcos, The University of Texas at Dallas, Richardson, Texas 75080, King Abdullah University of Science and Technology, Univ of Texas, Dallas, N.Chiao Tung U., UT Dallas, Inorganic Chemistry and Catalysis Group, Utrecht University, Electrical & Computer Engineering, Baylor University, Department of Materials Science and NanoEngineering, Rice University, University of Texas at Arlington, University of Chicago, The University of Mississippi, Astronomical Observatory, Warsaw University, Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, Rochester Institute of Technology, California Institute of Technology, University of Houston, NASA-GSFC and UMBC, MD, Virginia Tech, VA, Texas Christian University, The University of Texas at San Antonio, Department of Physics, Teivecca Nazarene University, Weatherford College, Air Force Research Laboratory, Sensors Directorate, WPAFB, OH, USA, Air Force Research Laboratory, Directed Energy Directorate, KAFB, NM, US, Department of Physics & Astronomy, University of Texas at San Antonio TX, USA, University of Arizona, University of North Carolina at Chapel Hill, Stanford University, Harvard Center for Astrophysics, Texas A\&M University, UTSW, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, Boston College, Chestnut Hill, Massachusetts 02467, Naval Research Laboratory, Washington, D.C. 20375

  • Qiye Zheng

    Santa Fe Institute, Baylor University, University of Texas at Dallas, Department of Chemistry, The University of Texas at Austin, Jozef Stefan Institute, Texas A&M University-Commerce, Commerce, Texas 75429, Cyclotron Institute, Texas A&M University, College Station, Texas 77843, Texas A&M University, Department of Physics, Texas State University, Department of Physics, Baylor University, University of Texas at El Paso, Univ of Texas, El Paso, University of Science and Technology of China, The University of Texas at Dallas, Faculty, None, Southwestern University, Texas State University, Texas A&M University - Commerce, UT Southwestern Medical Center, National High Magnetic Field Laboratory, The Cyclotron Institute at Texas A&M University, Department of Biological Sciences, Texas State Univ-San Marcos, The University of Texas at Dallas, Richardson, Texas 75080, King Abdullah University of Science and Technology, Univ of Texas, Dallas, N.Chiao Tung U., UT Dallas, Inorganic Chemistry and Catalysis Group, Utrecht University, Electrical & Computer Engineering, Baylor University, Department of Materials Science and NanoEngineering, Rice University, University of Texas at Arlington, University of Chicago, The University of Mississippi, Astronomical Observatory, Warsaw University, Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, Rochester Institute of Technology, California Institute of Technology, University of Houston, NASA-GSFC and UMBC, MD, Virginia Tech, VA, Texas Christian University, The University of Texas at San Antonio, Department of Physics, Teivecca Nazarene University, Weatherford College, Air Force Research Laboratory, Sensors Directorate, WPAFB, OH, USA, Air Force Research Laboratory, Directed Energy Directorate, KAFB, NM, US, Department of Physics & Astronomy, University of Texas at San Antonio TX, USA, University of Arizona, University of North Carolina at Chapel Hill, Stanford University, Harvard Center for Astrophysics, Texas A\&M University, UTSW, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, Boston College, Chestnut Hill, Massachusetts 02467, Naval Research Laboratory, Washington, D.C. 20375

  • Qiye Zheng

    Santa Fe Institute, Baylor University, University of Texas at Dallas, Department of Chemistry, The University of Texas at Austin, Jozef Stefan Institute, Texas A&M University-Commerce, Commerce, Texas 75429, Cyclotron Institute, Texas A&M University, College Station, Texas 77843, Texas A&M University, Department of Physics, Texas State University, Department of Physics, Baylor University, University of Texas at El Paso, Univ of Texas, El Paso, University of Science and Technology of China, The University of Texas at Dallas, Faculty, None, Southwestern University, Texas State University, Texas A&M University - Commerce, UT Southwestern Medical Center, National High Magnetic Field Laboratory, The Cyclotron Institute at Texas A&M University, Department of Biological Sciences, Texas State Univ-San Marcos, The University of Texas at Dallas, Richardson, Texas 75080, King Abdullah University of Science and Technology, Univ of Texas, Dallas, N.Chiao Tung U., UT Dallas, Inorganic Chemistry and Catalysis Group, Utrecht University, Electrical & Computer Engineering, Baylor University, Department of Materials Science and NanoEngineering, Rice University, University of Texas at Arlington, University of Chicago, The University of Mississippi, Astronomical Observatory, Warsaw University, Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, Rochester Institute of Technology, California Institute of Technology, University of Houston, NASA-GSFC and UMBC, MD, Virginia Tech, VA, Texas Christian University, The University of Texas at San Antonio, Department of Physics, Teivecca Nazarene University, Weatherford College, Air Force Research Laboratory, Sensors Directorate, WPAFB, OH, USA, Air Force Research Laboratory, Directed Energy Directorate, KAFB, NM, US, Department of Physics & Astronomy, University of Texas at San Antonio TX, USA, University of Arizona, University of North Carolina at Chapel Hill, Stanford University, Harvard Center for Astrophysics, Texas A\&M University, UTSW, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, Boston College, Chestnut Hill, Massachusetts 02467, Naval Research Laboratory, Washington, D.C. 20375

  • Qiye Zheng

    Santa Fe Institute, Baylor University, University of Texas at Dallas, Department of Chemistry, The University of Texas at Austin, Jozef Stefan Institute, Texas A&M University-Commerce, Commerce, Texas 75429, Cyclotron Institute, Texas A&M University, College Station, Texas 77843, Texas A&M University, Department of Physics, Texas State University, Department of Physics, Baylor University, University of Texas at El Paso, Univ of Texas, El Paso, University of Science and Technology of China, The University of Texas at Dallas, Faculty, None, Southwestern University, Texas State University, Texas A&M University - Commerce, UT Southwestern Medical Center, National High Magnetic Field Laboratory, The Cyclotron Institute at Texas A&M University, Department of Biological Sciences, Texas State Univ-San Marcos, The University of Texas at Dallas, Richardson, Texas 75080, King Abdullah University of Science and Technology, Univ of Texas, Dallas, N.Chiao Tung U., UT Dallas, Inorganic Chemistry and Catalysis Group, Utrecht University, Electrical & Computer Engineering, Baylor University, Department of Materials Science and NanoEngineering, Rice University, University of Texas at Arlington, University of Chicago, The University of Mississippi, Astronomical Observatory, Warsaw University, Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, Rochester Institute of Technology, California Institute of Technology, University of Houston, NASA-GSFC and UMBC, MD, Virginia Tech, VA, Texas Christian University, The University of Texas at San Antonio, Department of Physics, Teivecca Nazarene University, Weatherford College, Air Force Research Laboratory, Sensors Directorate, WPAFB, OH, USA, Air Force Research Laboratory, Directed Energy Directorate, KAFB, NM, US, Department of Physics & Astronomy, University of Texas at San Antonio TX, USA, University of Arizona, University of North Carolina at Chapel Hill, Stanford University, Harvard Center for Astrophysics, Texas A\&M University, UTSW, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, Boston College, Chestnut Hill, Massachusetts 02467, Naval Research Laboratory, Washington, D.C. 20375

  • Lloyd Lumata

    The University of Texas at Dallas, Univ of Texas, Dallas