Dynamic Nuclear Polarization of 23Na and 13C Nuclear Spins at 4.6T and 1.25 K

Dynamic Nuclear Polarization (DNP) is a hyperpolarization technique used to amplify the inherently weak magnetization of nuclei by transferring the near unity polarization of a free electron to the nuclei using an external microwave source at low temperatures and high magnetic fields. The strength of this transfer is dependent on many factors including free radicals and solvents. In this work we attempt to maximize the polarization of the spin active 13C and 23Na nuclei in Sodium acetate at 4.6T and 1.25K. We accomplish this by varying combinations of the solvent, the free radical, and the labeling of the nuclei. We expect this system will fall under the thermal mixing regime of DNP where the physics is described thermodynamically by coupled thermal reservoirs representing both nuclear and electron spin systems. We expect that removing the carbon labeling will improve sodium DNP due to the removal of a coupled reservoir of carbon nuclei from the system. The results will be discussed.