Applications of dissolution dynamic nuclear polarization in chemistry and biochemistry

• Published in: Magnetic resonance in chemistry Vol. 56; no. 7; pp. 566 - 582
• Main Authors: Zhang, Guannan, Hilty, Christian
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.07.2018
• Subjects: Biomedical materials; Correlation analysis; Dissolution; dissolution dynamic nuclear polarization; hyperpolarization; Image resolution; Molecular chains; NMR spectroscopy; Nuclear reactions; Nuclear spin; Organic chemistry; Polarization; Polarization (spin alignment); Reaction kinetics; Signal to noise ratio; Time dependence; Windows (intervals); dissolution dynamic nuclear polarization; hyperpolarization
• ISSN: 0749-1581; 1097-458X
• DOI: 10.1002/mrc.4735

Sensitivity of detection is one of the most limiting aspects when applying NMR spectroscopy to current problems in the molecular sciences. A number of hyperpolarization methods exist for increasing the population difference between nuclear spin Zeeman states and enhance the signal‐to‐noise ratio by orders of magnitude. Among these methods, dissolution dynamic nuclear polarization (D‐DNP) is unique in its capability of providing high spin polarization for many types of molecules in the liquid state. Originally proposed for biomedical applications including in vivo imaging, applications in high resolution NMR spectroscopy are now emerging. These applications are the focus of the present review. Using D‐DNP, a small sample aliquot is first hyperpolarized as a frozen solid at low temperature, followed by dissolution into the liquid state. D‐DNP extends the capabilities of liquid state NMR spectroscopy towards shorter timescales and enables the study of nonequilibrium processes, such as the kinetics and mechanisms of reactions. It allows the determination of intermolecular interactions, in particular based on spin relaxation parameters. At the same time, a challenge in the application of this hyperpolarization method is that spin polarization is nonrenewable. Substantial effort has been devoted to develop methods for enabling rapid correlation spectroscopy, the measurement of time‐dependent signals, and the extension of the observable time window. With these methods, D‐DNP has the potential to open new application areas in the chemical and biochemical sciences. Dissolution dynamic nuclear polarization, providing high spin polarization for many types of molecules in the liquid state, extends the capabilities of liquid state NMR spectroscopy towards shorter timescales and enables the study of nonequilibrium processes and intermolecular interactions. At the same time, methods developed for enabling rapid correlation spectroscopy, the measurement of time‐dependent signals, and the extension of the observable time window, open new application areas of dissolution dynamic nuclear polarization in the chemical and biochemical sciences.