Chapter 8: Dynamic Nuclear Polarization

In this chapter, dynamic nuclear polarization (DNP) is introduced as an effective tool to enhance the sensitivity of NMR, in particular in the solid-state under MAS. The relevant DNP mechanisms (i.e., solid effect, cross effect, and Overhauser effect) and the propagation of enhanced nuclear polarization via spin-diffusion is explained. Several polarizing agent (PA) classes are discussed in the context of DNP mechanism and their field or frequency profiles. In the final section practical aspects as well as contemporary DNP applications are presented, which highlight the tremendous potential DNP-enhanced MAS NMR bears towards challenging problems in structural biology.