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SYMR: Symposium Nuclear Magnetic Resonance: from Applications in Condensed-Matter Physics to New Frontiers
SYMR 5: Nuclear Magnetic Resonance: Frontiers and Applications
SYMR 5.9: Vortrag
Dienstag, 23. März 2010, 15:45–16:00, H48
Heparin-polynitroxide derivatives: biocompatible polarizing agents for dynamic nuclear polarization (DNP) — •Björn C. Dollmann1, Andrei L. Kleschyov2, Vasily Sen3, Valery Golubev3, Laura Schreiber4, Kerstin Münnemann1, and Dariush Hinderberger1 — 1Max Planck Institute for Polymer Research, Mainz, Germany — 2Second Department of Medicine, Johannes Gutenberg University, Mainz, Germany — 3Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Russia — 4Johannes Gutenberg University Medical Center, Mainz, Germany
A versatile and biocompatible class of spin-labeled macromolecules was investigated by electron spin echo-detected (ESE) electron paramagnetic resonance (EPR), continuous-wave (CW) EPR, double electron-electron resonance (DEER) and dynamic nuclear polarization (DNP). These heparin macromolecules could be utilized for in vivo magnetic resonance imaging (MRI DNP enhanced) and EPR imaging (EPRI). The distance distributions of the spin labels were measured and compared with the crystallographic structure of heparin. All presented heparin-polynitroxides show reasonably high 1H DNP enhancement factors up to E=−108. The heparin-polynitroxides intrinsically feature high dipolar electron spin-electron spin coupling frequencies νdd. Together with the finding that the best 1H-signal enhancements are found in the low concentration region, this proves the influence of the anisotropic electron spin distribution on DNP in liquids at room temperature.