Iron oxide magnetic nanoparticles based low-field MR thermometry
| Autor: | Pu Zhang, Jing Zhong, Wenzhong Liu, Yapeng Zhang, Silin Guo |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Condensed matter physics Field (physics) Mr thermometry Mechanical Engineering Iron oxide Bioengineering 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Magnetic field chemistry.chemical_compound Magnetization chemistry Mechanics of Materials Relaxation rate Magnetic nanoparticles General Materials Science Particle size Electrical and Electronic Engineering 0210 nano-technology |
| Zdroj: | Nanotechnology. 31(34) |
| ISSN: | 1361-6528 |
| Popis: | This paper reports on a highly accurate approach of magnetic resonance (MR) thermometry using iron oxide magnetic nanoparticles (MNPs) as temperature sensors. An empirical model for the description of the temperature dependent R 2 relaxation rate is proposed by taking into account the temperature sensitivity of the MNP magnetization. The temperature sensitivity of the MNP magnetization (η) and the temperature sensitivity of the R 2 relaxation rate (κ) are simulated with the proposed empirical models to investigate their dependence on the magnetic field and the particle size. Simulation results show the existence of optimal magnetic fields Hoη and Hoκ that maximize the temperature sensitivities η and κ. Furthermore, simulations and experiments demonstrate that the optimal magnetic field Hoη (Hoκ ) decreases with increasing the particle size. Experiments on temperature dependent R 2 relaxation rate are performed at different magnetic fields for MNP samples with different iron concentrations. Experimental results show that the proposed MR thermometry using MNPs as temperature sensors allows a temperature estimation accuracy of about 0.05 °C. We believe that the achieved approach of highly accurate MR thermometry is of great interest and significance to biomedicine and biology. |
| Databáze: | OpenAIRE |
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