Challenges for Molecular Magnetic Resonance Imaging (original) (raw)

Contents 1. Introduction 3019 2. Challenges in the Field of Paramagnetic T 1 Agents 3021 2.1. Optimizing the Rotational Mobility 3021 2.2. Effect of τ M on the Attainable Relaxivity 3022 2.3. Increasing Relaxivity through the Increase of the Hydration of the Paramagnetic Metal Ion 3023 2.4. Nanosized Systems 3023 2.5. Mn 2+-Complexes: An Alternative to Gd-Based Agents? 3024 2.6. Field-Dependence of Relaxivity 3024 2.7. Responsive Agents 3025 3. Challenges for T 2 Agents 3027 3.1. Iron Oxide Nanoparticles 3027 3.2. T 2 Agents: Alternatives to Iron Oxide Nanoparticles 3028 3.3. Magnetic Particle Imaging 3029 4. Challenges for CEST Agents 3029 4.1. Technical Issues 3029 4.2. Chemical Issues 3031 4.3. Biological Issues 3032 5. Challenges for Heteronuclear MR Imaging 3033 5.1. 19 F-Based Probes 3033 6. Challenges for Hyperpolarized Probes 3034 6.1. Brute Force 3034 6.2. Optical Pumping and Spin Exchange 3035 6.3. Dynamic Nuclear Polarization (DNP) 3035 6.4. para-Hydrogen Induced Polarization (PHIP) 3037 6.5. Use of Gd Contrast Agents with Hyperpolarized Substances 3038 6.6. Issues with Hyperpolarized Agents 3038 7. Concluding Remarks 3038 8. Acknowledgments 3039 9. References 3039