NMR Spectrometry in TBSI
Postgrad Anna Hastings and the 800 MHz NMR spectrometer; photograph by Matthew Thompson
By Dr Keith Alden
Nuclear magnetic resonance spectroscopy is a technique for obtaining qualitative and quantitative information about the structure of molecules by enabling the natural magnetism of atomic nuclei to interact with a generated magnetic field. This technique exploits atomic nuclei with non-zero magnetic moments to act as tiny probes for the detection of the local structure, dynamics, reaction state, and chemical environment within molecules. NMR spectra are unique, well-resolved, analytically tractable, and inherently quantitative, thereby well-suited for confirming the identity-authenticity of substances, even in mixtures (for example, in NMR metabolomics).
Because it is extremely sensitive to changes in local environments, identical functional groups with differing neighbours still give distinguishable signals, allowing the monitoring of structural dynamics and/or ligand binding to macromolecules. NMR is also a valuable tool for studying local structure and dynamics in a variety of solid systems. Objects of such solid-state NMR studies in materials science are inorganic/organic aggregates in crystalline and amorphous states, composite materials, heterogeneous systems including liquid or gas components, suspensions, and molecular aggregates with dimensions on the nanoscale. Due in part to major technological developments in probe design, signal processing, and computational power, potential applications of NMR include structural biology, metabolomics, food science, toxicology, natural products research, pharmaceutical reaction and process monitoring, and organic chemistry.
TBSI houses an Agilent Technologies Ultra High Field (UHF) 800 MHz Nuclear Magnetic Resonance system — the highest field NMR facility in Ireland with both liquid and solid state capabilities. The system is equipped with a number of different probes, including a cryogenically cooled triple resonance ColdProbe that provides significant sensitivity gains and is ideal for low concentration samples in either non-ionic or highly ionic solvents. The 800 MHz ASC (Actively Shielded Compact) magnet draws on the latest super conducting wire technology to make this super compact shielded magnet which operates at a temperature of 4.2 Kelvin (K). The NMR system also has a 12 station auto-loader.
Some selected publications resulting from this facility:
(1) Biomolecular structure and dynamics: Brisuda A et al, Nature Comm In press, 2021; Kim D-H et al, Biomolecules 10: 428, 2020; Kandiyal PS et al, in McManus J (ed) Protein Self-Assembly. Meth Mol Biol 2039: 173-83, 2019.
(2) NMR Metabolomics: McGettrick AF, et al, PNAS E7778-E77787, 2016; Al Ani et al, Sci Rep 6: 38074, 2016.
(3) Solid-state NMR: Shanmugaraju S et al, J Mater Chem 5: 25014, 2017; Meazzini I et al, Macromolecules50: 4235–4243, 2017.
(4) Macromolecule-Ligand binding: Ho JCS et al, J Biol Chem 288: 17480-71, 2013
(5) Small molecule structure/dynamics: Canestrari D et al, Chem Sci 10: 9042-9050, 2019.
With a view to broaden the user-base and encourage exploratory experiments, TBSI has completely revamped the charges for use. If you are interested in seeing how high resolution NMR or NMR in general could compliment or aid your research please contact:
Dr Keith Alden is TBSI Operations Manager