Higher, Better, Faster!? Ultra-high Field Magnetic Resonance Imaging and Spatially Resolved Spectroscopy

Summary:

Magnetic Resonance techniques are very valuable for non-invasive identification, detection and imaging of chemical compounds. However, magnetic resonance methods are relatively insensitive, i.e. have a high limit of detection, so only high concentrations of compounds can be detected. In Magnetic Resonance Imaging (MRI) applications the consequence is that only relatively low image resolutions can be obtained, or extremely long measurement times are needed. In practice, MRI mainly detects the signal of water molecules. To increase the sensitivity of MRI, ultra-high magnetic field strengths can be used. One of strongest magnets currently available was used in this thesis to test the potential and challenges of ultra-high field MRI for a variety of samples, ranging from biofilms growing on electrode material used in waste-water treatment to root nodules of plants involved in nitrogen fixation. Spatially resolved spectroscopy at ultra-high field was investigated for an additional advantage next to higher sensitivity, namely the opportunity to identify and discriminate different chemical compounds at relatively low concentrations.