Time-resolved NMR by dynamic nuclear polarization

PHYS 241

Christian Hilty, chilty@mail.chem.tamu.edu, Sean Bowen, sbowen@mail.chem.tamu.edu, and Haifeng Zeng, hzeng@mail.chem.tamu.edu. Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, TX 77843
Among spectroscopic techniques, nuclear magnetic resonance (NMR) yields an exceptional wealth of information on molecular structure and dynamics. However, due to sensitivity constraints, signal averaging commonly needs to be applied, which restricts measurements to samples under equilibrium conditions. Hyperpolarization techniques, such as dynamic nuclear polarization (DNP) can increase the signal of an NMR experiment by several orders of magnitude. Due to a high signal-to-noise ratio achievable in a single scan, typically equivalent to several months of conventional signal averaging, DNP-NMR is ideally suited for the time-resolved investigation of transient processes. Using a stopped-flow system that we have constructed for this purpose, we present applications of DNP-NMR to the measurement of enzyme kinetics, and the time-resolved observation of chemical reactions. We also show preliminary data that illustrates the promise of this method for the investigation of protein folding.