Biomedical Magnetic Resonance Facility

Dr Ghadirian

The Biomedical Magnetic Resonance Facility

The internationally renowned Western Sydney University, Biomedical Magnetic Resonance Facility (BMRF) specialises in assisting researchers, students and industry with a variety of magnetic resonance-based biological, chemical and medical analyses.

  • The facility offers fee for service work or training on the instruments for external users.
  • The BMRF is capable of conducting all standard contemporary nuclear magnetic resonance (NMR) experiments including High Resolution Magic Angle Spinning (HRMAS).
  • Magnetic resonance imaging (MRI) and NMR diffusion measurements are particular specialties.
  • The BMRF also has high-level expertise for analysing the resulting data.
  • The BMRF is a node of the National Imaging Facility (NIF). (opens in a new window)
  • The BMRF is situated on the Campbelltown Campus in Building 17.

Instrumentation

STELAR Fast Field Cycling Relaxometer
Western Sydney University will soon be home to the first fast field cycling nuclear magnetic resonance spectrometer (FFC NMR) in Australia.
Many of the most important chemical processes involve the slow dynamics of molecules that occur in the range between nanoseconds and milliseconds. This includes a diverse range of phenomena from clinical to industrial importance such as MRI contrast and the development of new MRI contrast agents, to the durability of concrete, filtration and even food spoilage. Such slow motions are difficult to measure at the fixed high magnetic field strengths of traditional NMR spectrometers (normally > 7 T) and Magnetic Resonance Imagers (typically 1.5 or 3 T). However, measuring the longitudinal relaxation time ("T1") of a molecule as a function of the observation frequency (especially at lower frequencies) - known as nuclear magnetic resonance dispersion or NMRD - is a particularly powerful means for probing slow molecular dynamics. The FFC NMR allows the NMRD profile to be measured from about 10-6 T up to the maximum field allowed by the magnet (3 T in our case). Examples of problems addressed using FFC NMR include filtration, imbibition, conduction and wettability, protein hydration, dynamics of polymers and liquid crystals, MRI contrast agents, durability of cements and concretes, determination of oil to water ratios in rock cores, filtration and water purification in soils, catalysis.
BRUKER AVANCE III 600 MHz Wide Bore NMR/MRI Spectrometer (14.1 T) Equipped with high field XYZ gradient amplifiers capable of generating up to 3000 G/cm. It is equipped with various probes and accessories that enable it to be used for a wide range of NMR experiments such as diffusion, micro-imaging, and high-resolution protein structure determination.
BRUKER AVANCE II 500 MHz Wide Bore NMR/MRI Spectrometer (11.7 T) Equipped with high field XYZ gradient amplifiers capable of generating up to 3000 G/cm. It is equipped with various probes and accessories that enable it to be used for a wide range of NMR experiments such as diffusion, micro-imaging, high-resolution MAS, and high-resolution protein structure determination.
BRUKER AVANCE 400 MHz NMR Spectrometer (9.4 T) Equipped with high resolution gradients (i.e., up to ~55 G/cm). Suited for heteronuclear NMR studies and for diffusion studies of small molecules to moderately sized polymers.
VARIAN MERCURY 300 MHz NMR Spectrometer (7.0 T) Equipped with 4-nuclei inverse probe with z-axis gradients. The probe was specially modified to simultaneously tune to four nuclei namely 1H, 19F, 13C and 31P. Suited for routine 1D and 2D NMR experiments.
MAGRITEK EARTH FIELD NMR 
(58 µT / 0.58 gauss)
A simple instrument which can be used for NMR, diffusion and imaging experiments. Can also be used for some 'off the wall' experiments.
Latitude: 34.06821999
Longitude: 150.78963912
Sea Level: 88 metres
THERMOFISHER QUANTUM GX microCT This imaging system provides high-resolution images at an X-ray dose low enough to enable true longitudinal imaging capability. The Quantum GX offers the highest resolution among all the microCT scanners for pre-clinical imaging (4.5 micrometre voxels). The wide field of view (FOV) scanning at 36 mm and 72 mm allows for high resolution imaging of mice, rats and rabbits.

Current Projects in the Facility

NanoRatchet - Available for Licensing

University of Western Sydney inventors Dr Scott A. Willis, Prof William S. Price, A/Prof Gary R. Dennis and Dr Gang Zheng have developed an original design for a new separation technology called the NanoRatchet. The NanoRatchet can be constructed from nano-materials and upwards to achieve continuous flow separations at the molecular level through to (macroscopic) particle separations. (NanoRatchet information brief) (NanoRatchet information brief) (PDF, 187.49 KB)  (opens in a new window)

Water Control Technique - Available for Licensing

Researchers at the University of Western Sydney (Dr Gang Zheng, Prof William S. Price and Dr Allan M. Torres) have developed a new method of water signal control/ suppression to prevent the problematically strong water signal in solution-state NMR, with no or minimal loss of features of interest.
The newly developed WaterControl technique provides highly selective and quantifiable water signal control/suppression suitable for protein/DNA/RNA structure determination, metabolomics, magnetic resonance spectroscopy (MRS) and chemical shift imaging (CSI).  (Water Control information brief)       (Water Control information brief) (PDF, 336.26 KB)  (opens in a new window)

Force in NMR

Force Predicting a small force over typically micrometre length scales by diffusing species in a bounded geometry under certain nuclear magnetic resonance pulsed magnetic field gradient sequences. My calculations reveal that the total magnetisation energy in a pore under the influence of a pulsed gradient will be distance-dependent thus resulting in a force acting on the boundary. It is shown that this effect of the magnetisation of diffusing particles will appear as either an attractive or repulsive force depending on the geometry of the pore and magnetic properties of the material. It is shown that the force decays exponentially in terms of the spin-spin relaxation.

Brain Structure and Volume Variation of Agamid Lizards under Contrasting Natural and Sexual Selection.

Three orthogonal slices from the three dimensional atlas dataset 

Three orthogonal slices from the three dimensional atlas dataset

This project investigated how sociality, sexual selection and natural selection act on brain structure in Australian agamid lizards. Using the 500 MHz MRI, over 280 lizard brains were imaged with 100 µm isotropic voxel resolution. A further 10 brains were scanned at 50 µm isotropic voxel resolution to create the first ever 3D lizard brain atlas.

Investigating More Realistic Pores in Diffusion NMR.

Reflecting_concentric_cylindrical_pore Simulated spin-echo attenuation data for diffusion in a reflecting concentric cylindrical pore, whose symmetrical axis is oriented at f = 45° with respect to the magnetic gradient (q). simulated spin-echo attenuation data 
Cuboid Simulated spin-echo attenuations in a reflecting (solid line) and relaxing (dotted line) cuboid with dimensions a = 150, b = 100 and c = 130 μm , oriented in an arbitrary direction of θ = 75°, ϕ = 39° and ω = 55° from the magnetic gradient Rectangle

NMR (MRI) Signal Processing

enhance We are currently working on an NMR signal enhancement project that can be also used for imaging (e.g. MRI). We were able to modify the powerful Singular Value Decomposition method algorithm in signal processing. Our algorithm has many advantages over the previous one, because it does not require much information about the pre-processed signal or image. More work is still needed to complete the algorithm.

Imaging Placental Function

Preeclampsia is a serious medical condition suffered by some pregnant women with abnormal placental development implicated in its aetiology. It is a leading cause of morbidity and mortality in both mothers and infants and is characterised by high blood pressure and protein in the urine. In this project, T2 mapping, which is sensitive to metabolic variables such as oxygenation and pH, was used to investigate placental changes in two well established models of preeclampsia: the Reduced Uterine Perfusion (RUPP) and the TNF-α infusion models.
R2 (1/T2) map of gestational day 17.5 normal pregnant C57BL/6JArc mouse showing T2 contrast in the placenta A) before and B) after cessation of blood flow.
Further research projects modifying and optimizing sequence acquisitions and performing post-acquisition processing in order to obtain multi compartment information (vascular and extravascular) and information on dynamic responses to changes in oxygenation analysis are available. Definitive analysis of changes in tissue pH by MRI and spectroscopic identification of possible metabolic biomarkers of disease are studies that are also earmarked.