Research

Nuclear Magnetic Resonance (NMR) spectroscopy takes advantage of the intrinsic nuclear spin of certain atomic nuclei (e.g. ¹H, ¹¹B, ¹³C, ¹⁵N, ¹⁹F, ²⁹Si, and ³¹P) and their sensitivity to their electronic environment to elucidate molecular structure, understand dynamics, investigate reaction kinetics, probe molecular interactions, and quantitate purity. NMR is unique in its ability to provide a nondestructive method of providing a detailed picture of structure and dynamics of materials in either the solid- or solution-state.

 

Today, NMR has become a sophisticated and powerful analytical technology that has found a variety of applications in many disciplines of scientific research, medicine, and various industries. Modern NMR spectroscopy has been emphasizing the application in biomolecular systems and plays an important role in structural biology. With developments in both methodology and instrumentation in the past two decades, NMR has become one of the most powerful and versatile spectroscopic techniques for the analysis of biomacromolecules, allowing characterization of biomacromolecules and their complexes up to 100 kDa. Together with X-ray crystallography, NMR spectroscopy is one of the two leading technologies for the structure determination of biomacromolecules at atomic resolution. In addition, NMR provides unique and important molecular motional and interaction profiles containing pivotal information on protein function. The information is also critical in drug development. Some of the applications of NMR spectroscopy are listed below:

• Small Molecules: The structure of unknown compounds can be determined using a series of 1D and 2D NMR experiments. The amount of the compound and its purity can be determined using quantitative NMR.
• Kinetics: NMR can be used to follow reaction kinetics to investigate reaction mechanisms.
• Diffusion: The rate of diffusion of molecules in solution can be measured to determine properties like molecular weight, ligand binding, molecular association (i.e. dimerization, trimerization).
• Solid-State: NMR is not limited to samples in solution. Structural and dynamic information can be obtained from solids and semi-solids. 
• Solution structure: The only method for atomic-resolution structure determination of biomacromolecules in aqueous solutions under near physiological conditions or membrane mimeric environments.
• Molecular dynamics: The most powerful technique for quantifying motional properties of biomacromolecules.
• Protein folding: The most powerful tool for determining the residual structures of unfolded proteins and the structures of folding intermediates.
• Ionization state: The most powerful tool for determining the chemical properties of functional groups in biomacromolecules, such as the ionization states of ionizable groups at the active sites of enzymes.
• Weak intermolecular interactions: Allowing weak functional interactions between macrobiomolecules (e.g., those with dissociation constants in the micromolar to millimolar range) to be studied, which is not possible with other technologies.
• Protein hydration: A power tool for the detection of interior water and its interaction with biomacromolecules.
• Hydrogen bonding: A unique technique for the DIRECT detection of hydrogen bonding interactions.
• Drug screening and design: Particularly useful for identifying drug leads and determining the conformations of the compounds bound to enzymes, receptors, and other proteins.
• Native membrane protein: Solid state NMR has the potential for determining atomic-resolution structures of domains of membrane proteins in their native membrane environments, including those with bound ligands.
• Metabolite analysis: A very powerful technology for metabolite analysis.
• Chemical analysis: A matured technique for chemical identification and conformational analysis of chemicals whether synthetic or natural.
• Material science: A powerful tool in the research of polymer chemistry and physics.
• For Protein NMR sample requirements, see the following link: Protein sample preparation.

Useful NMR Links:

• NMR Chemical Shifts of Trace Impurities. If you are trying to figure out what those impurities are, this is a great start.  The paper lists the ¹H and ¹³C chemical shifts of common impurities in a variety of NMR solvents.
• Prof. Hans Reich's collection of various topics on NMR. Most of this content originated from his Chem 605 Course at the University of Wisconsin - Madison. Excellent resource for understanding chemical shifts, relaxation, and understanding/interpreting NMR data. Includes large database of ¹H, ¹¹B, ¹³C, ¹⁹F, ³¹P, and ⁷⁷Se NMR chemical shifts. 

• High-Resolution NMR Techniques in Organic Chemistry. The definitive book on understanding NMR for an experimental point of view.