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Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
Published on: September 26, 2016
Development of a 3-D, multi-nuclear continuous wave NMR imaging system
Andrew J Fagan1, Gareth R Davies, James M S Hutchison
1Department of Bio-Medical Physics and Bio-Engineering, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
Summary
A new 3-D, multi-nuclear continuous wave NMR imaging (CW-NMRI) system effectively images materials with short T(2) relaxation times. This advanced CW-NMRI technology demonstrates sensitivity to elemental composition and pore structure in various materials.
Area of Science:
- Materials Science
- Nuclear Magnetic Resonance Imaging
Background:
- Continuous Wave Nuclear Magnetic Resonance Imaging (CW-NMRI) systems are valuable for material characterization.
- Previous prototypes faced limitations with microphonic noise and imaging materials with very short T(2) relaxation times.
Purpose of the Study:
- To develop and demonstrate a 3-D, multi-nuclear CW-NMRI system capable of imaging materials with short T(2) relaxation values.
- To assess the system's sensitivity to elemental composition and material structure.
Main Methods:
- Development of a 3-D, multi-nuclear CW-NMRI system with modified resonators and gradient/field offset coils.
- Minimization of microphonic noise in the system design.
- Imaging of various materials including cements, Li(2)CO(3), and polymers.
Main Results:
- Successful imaging of chemically combined (27)Al in refractory cement, showing sensitivity to Al content.
- Investigation of (23)Na penetration in ordinary Portland cement (OPC), correlating with pore size distribution.
- Imaging of solid (13)C in carbonated cement, (7)Li in Li(2)CO(3), and achieving 1mm spatial resolution in a polymer with T( *)(2) = 16.3 µs.
Conclusions:
- The developed 3-D, multi-nuclear CW-NMRI system is effective for characterizing diverse materials, including those with short T(2) relaxation times.
- The system demonstrates high sensitivity to elemental composition and microstructural features like pore size distribution.
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