Abstract
Abstract: The effect of high volume fraction of magnetic nanoparticles (MNP) on Magnetic Resonance Imaging (MRI) transverse relaxation rates (R2 = 1/T2 and R2* = 1/T2*) is investigated using Monte Carlo (MC) simulations. Theoretical models assume that particles occupy a small volume fraction of the sample space. Results presented in this work show that models based on both motional averaged (MAR) and static dephasing (SDR) regimes respectively underestimate and overestimate relaxation rates at large volume fractions. Furthermore, both R2* and R2* become echo-time dependent. This suggests that diffusion is involved with larger echo-times producing smaller relaxation rates due to better averaging of the magnetic field gradients. Findings emphasize the need for the models to be modified to take account of high particle concentration especially important for application involving clustering and trapping of nanoparticles inside cells. This is important in order to improve the design process of MNP Contrast Agents.
Original language | English |
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Article number | 101 |
Journal | Applied Sciences (Switzerland) |
Volume | 8 |
Issue number | 1 |
DOIs | |
Publication status | Published - Jan 11 2018 |
Keywords
- Contrast agent
- MAR
- MRI
- Magnetic nanoparticles
- Monte Carlo
- SDR
- T2
ASJC Scopus subject areas
- General Materials Science
- Instrumentation
- General Engineering
- Process Chemistry and Technology
- Computer Science Applications
- Fluid Flow and Transfer Processes