J.N.Junk, M. and M.J.N. Junk, Thermoresponsive Spin-Labeled Hydrogels as Separable DNP Polarizing Agents Assessing the Functional Structure of Molecular Transporters by EPR Spectroscopy. 2012: p. 133-148.
Dynamic nuclear polarization (DNP) is a commonly applied NMR hyperpolarization technique, which is based on the polarization transfer from electron spins to nuclear spins. While DNP allows a significant enhancement of NMR signals by several orders of magnitude, major drawbacks of the method include enhanced nuclear relaxation times due to the presence of unpaired electrons and the toxicity of radicals, which is the limiting factor for in vivo applications in magnetic resonance imaging. Thus, an efficient separation of the polarization agent is a key requirement for possible applications in medicine. In this chapter, the application of spin-labeled thermoresponsive hydrogels as polarizing agents for dynamic nuclear polarization is explored.