Equipment Equipment

Nuclear Magnetic Resonance (NMR) encompasses several powerful structural and analytical methodologies which are capable of providing atomic level information about molecules.

For example, it can determine the numbers of particular atoms within a molecule, their chemical environments and how they are interconnected and spatially arranged based on their magnetic properties.

The nuclear magnetic resonance spectroscopy facility at UEA enables structural and dynamic studies on substances ranging from small molecule pharmaceuticals and polymers to complex biomolecules, solids and colloids. The facility provides unique opportunities to study molecules, their assemblies, colloids, soft solids and functional materials over different time scales and physical states.

The facility includes a range of state-of-the-art NMR spectrometers capable of elucidating a variety of compounds and materials in solution, gels, colloidal systems and in the solid state. The facility focuses on providing research expertise for problems where application of advanced NMR methods is essential. Depending on the type of application of NMR required we will offer expert support in assessing the research problem, access to equipment, data collection and advanced analysis of results.

All enquiries are welcome and should initially be addressed to Colin Macdonald, Facilities Manager c.macdonald@uea.ac.uk 01603 592024

We have the following equipment available for use

High field (800 MHz and 500 MHz) spectrometers for biomolecular NMR

Both are 3-channel multinuclear instruments and are equipped with inverse triple resonance (H/C/N) z-gradient probes. They are therefore able to perform an extensive range of powerful state-of-the-art multidimensional NMR experiments required for demanding applications in biomolecular NMR such as 2D, 3D, and 4D triple resonance experiments on isotopically enriched proteins. Together the spectrometers are typically used to study protein and carbohydrate structure/function relationships.

Furthermore the spectrometers are supported by a network of Linux workstations running various software packages for data processing, analysis, molecular graphics etc. e.g TopSpin/NMRPipe/CCPN Analysis/UNIO.

High-resolution (500 MHz and 400 MHz) NMR spectrometers for structural elucidation and analysis

All of these instruments are dual channel and have variable temperature capabilities. They are configured with autosamplers for medium throughput analysis and broad band tuneable probes enabling observation of the widest range of nuclei. They are programmed with a wide variety of NMR techniques in order to fully characterise and describe the systems under investigation.

Solid-state and gel NMR

400 MHz solid-state NMR spectrometer

- Triple channel spectrometer Bruker Avance III capable of studying nuclei with gyromagetic ratios from 14N to 31P, 19F, and 1H. 

- MAS probes with spinning rates up to 15 and 35 kHz. 

- Variable temperature operation

300 MHz solid-state NMR spectrometer

- Double channel Bruker Avance III spectrometer with multinuclear capability (1H/15N-31P)

- Variable temperature -50 to 80C

High-resolution MAS NMR (gel NMR)

- a 400 MHz triple resonance HR/MAS probe (1H-31P-13C, optimised for 13C);

- an 800 MHz double resonance HR/MAS probe (1H-13C, optimised for 13C).

 

NMR spectroscopy is the principle method of analysis for the characterisation and identification of organic compounds. Typical applications of solution-state NMR methods include:

Quantitative analysis of the content and purity of a sample

Determination of molecular structure of organic molecules using 1H and 13C atom focused methods to identify the carbon-hydrogen framework of an organic compound

Identification of molecular conformations

Studies of physical and chemical properties at the molecular level such as conformational exchange and phase transitions

Monitoring chemical processes and kinetics

Studies of aggregation of molecules and diffusion

When applied to proteins, NMR spectroscopy allows the determination of protein structures, study of dynamics from ps to second, and study of interactions with other proteins or small molecule ligands in solution. Other directions of research in this area include analysis of carbohydrates and polymers in solution.

The main capabilities of protein NMR in Norwich include:

Calculation of the structure of proteins in solution, using distance and torsion angle restraints, and other parameters measured by NMR.

Study of the dynamics of proteins in solution by measuring relaxation parameters which report on motions on the ps-ns timescale, and relaxation dispersion to report on dynamical processes in the ms timescale. This can be combined with hydrogen/deuterium exchange experiments to reveal how stable hydrogen bonds within the protein are and measure dynamics in a much longer timescale.

Study of  interactions of proteins with small or large molecules by NMR. NMR reports on individual atoms, and is therefore able to map each amino acid residue within the protein that is affected by each interaction.

 

A [1H, 15N}-TROSY (transverse relaxation optimised spectroscopy) spectrum of the protein SBDS (above) ) gives its signature pattern, a 29-kDa protein which is mutated in Shwachman-Bodian-Diamond syndrome, and the ribbon diagram structure of SBDS.

transverse relaxation optimised spectroscopy

Shwachman-Bodian-Diamond syndrome

Solid-state NMR spectroscopy has proven to be an important tool capable of deriving structural and dynamics information using relatively short-range magnetic interactions.

To derive such information this technique has to overcome the effect of anisotropic magnetic interactions which, although containing a wealth of structural information, lead to significant broadening of the peaks, often beyond the expected level of resolution. The prevalent approach for eliminating this problem lies in the application of magic angle spinning. This method is suitable not only for solids, but also for colloidal materials and gels.


NMR spectrum of periodic mesoporous organosilicas

1H-29Si HETCOR solid-state NMR spectrum of periodic mesoporous organosilicas proving heterogeneous distribution of functional groups in amorphous framework

We have developed research expertise in elucidation of structural and dynamic properties of different classes of advanced materials:

  • porous solids (zeolites, mesoporous silicas and polymers, metal-organic frameworks)
  • polymer based amorphous pharmaceutical dispersions
  • air and water sensitive materials
  • pharmaceuticals and composites

We also have a variable temperature capability and have expertise in in-situ solid-state NMR.

Study soft materials and gels

In addition to solid-state NMR capability, the NMR facility at UEA provides a unique opportunity to study soft materials and gels. The application of either traditional solution or solid-state NMR methods to such systems is limited and therefore the use of magic-angle spinning in combination with advanced high-resolution methods is required. The systems of interest in this area include hydrogels, liquid-solid composites, gels, emulsions and tissues. The experiments on such systems can be carried out both at 400 and 800 MHz.