During the last couple of years, we have been trying to understand the various stages of the DNP process leading to nuclear signal enhancements in static solid solutions, containing free organic radicals. Despite the fact that almost everything is known already, we have made an effort to clarify the basic spin dynamics resulting in these enhancements. For these studies, we performed...
Magnetic resonance spectroscopies can provide unique contributions to describe cellular processes. Magnetic resonance is indeed suitable not only for characterizing the structural and dynamical properties of biomolecules but, even more importantly, for describing transient interactions and functional events with atomic resolution possibly in a cellular context. This requires the development of...
For application of electrolyte materials in energy storage devices their transport properties are essential. Multinuclear (e.g. 1H, 7Li, 19F) Pulsed-Field-Gradient (PFG)-NMR diffusion has become a widely used method in this field. However, to identify the conductivity contribution of specific ion species remains a challenge, since the electrophoretic mobility µ...
Understanding the mechanisms of membrane proteins entails complementing static structures with the conformational changes in the structure. Recent advances in Double Electron-Electron Resonance (DEER) spectroscopy along with computational methods to generate restrained models of proteins are enabling unprecedented insights into the conformational dynamics of active transporters. My laboratory...
Dynamic Nuclear Polarization (DNP) has recently evolved into a cornerstone technology to overcome the sensitivity limitations of solid-state NMR. This technique, originally developed for low magnetic fields, has been shown to be applicable at high fields, opening new avenues in materials and life sciences. In this presentation we will review some recent advances from high magnetic field (18.8...
Diffusion MRI is today used in clinical routine for detecting stroke and grading prostate tumors, as well as in clinical research studies of for instance neurological diseases and normal brain development. The overwhelming majority of the diffusion MRI measurements are performed with motion encoding by the most basic form of the pulsed-gradient spin echo sequence from the mid-60s, which is...
Biofilms are implicated in serious infectious diseases and have emerged as a target for anti-infectives. Our research program is inspired by the challenge and importance of elucidating chemical structure and function in complex biological systems and we strive to transform our discoveries into new therapeutic strategies. We have introduced new approaches integrating solid-state NMR with...
A broad effort is underway to improve the sensitivity of nuclear magnetic resonance through the use of dynamic nuclear polarization (DNP). Nitrogen-vacancy (NV) centers in diamond offer an appealing platform because these paramagnetic defects show efficient optical pumping at room temperature. This presentation focuses on the spin dynamics of NVs coupled to substitutional nitrogen (the so...
NMR spectroscopy presents a non-invasive detection technique for molecular structure elucidation and dynamic effect analyses. In general NMR applications, spectral resolution is the key index determining the availability of resulting spectra. Due to limited chemical shift ranges and appended J coupling splittings, conventional 1H NMR spectra are subject to spectral congestions in complex...
In the highest-field NMR magnets (currently 23.5 T, 1 GHz proton NMR frequency), the Larmor precession frequency for spin-1/2 electrons is 660 GHz. The recently-demonstrated 32 T superconducting magnet at MagLab in Tallahassee pushes the Larmor frequency to nearly 900 GHz. However, at the present time, it is difficult to generate a programmable sequence of phase-coherent narrow-band pulses...
Current NMR methods for studying proteins are primarily focused on backbone resonances and on methyl bearing side chains. In contrast, NMR of aromatic side chains has been less pursued although these moieties form a large portion of the hydrophobic protein cores. This is in part due to the complexity of aromatic side-chain spectra, which appear in a narrow and crowded spectral region....
The smaller chemical shift dispersion and the pairwise interaction among all the abundant nuclear spins of the molecule renders 1H NMR spectrum highly complex, severely hindering the straightforward analysis and the accurate determination of homo- and hetero- nuclear scalar couplings. The inherent insentitivy of NMR technique poses additional challenge. We have manipulated the spin dynamics...
The nitrogen-vacancy (NV) centre in diamond is an optically addressable single spin-1 electronic system with relatively long coherence persisting at room temperature, making it ideal for a range of nanoscale quantum sensing applications. The NV system is sensitive to local magnetic and electric fields, as well as material properties such as strain and temperature. An exciting direction is the...
Proteins are inherently dynamic, exhibiting conformational freedom on many timescales,1 implicating structural rearrangements that play a major role in molecular interaction, thermodynamic stability and biological function. Intrinsically disordered proteins (IDPs) represent extreme examples where flexibility defines molecular function. IDPs exhibit highly heterogeneous local and...