T2 relaxation induced by clusters of superparamagnetic nanoparticles:: Monte Carlo simulations
T2 relaxation induced by clusters of superparamagnetic nanoparticles:: Monte Carlo simulations
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DOI：
10.1016/j.mri.2008.01.039
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发表时间：
2008-09-01
影响因子：
2.5
通讯作者：
Jasanoff, Alan
中科院分区：
文献类型：
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作者：
Matsumoto, Yuri;Jasanoff, Alan
在磁共振实验中，团簇对超顺磁性纳米粒子诱导的横向(7)弛豫有很大的影响。在这项研究中，我们使用蒙特卡罗模拟方法系统地研究了T-2值与纳米粒子团簇几何参数之间的关系。我们将松弛计算为粒子大小、每个簇的粒子数量、粒子间距离和簇形状(紧凑型与线型)的函数。我们发现，致密团簇引起的弛豫相当于大小相似的单个粒子。对于小颗粒，团簇的形状和密度对T-2有显著影响。相反，对于较大的颗粒，T-2弛豫相对独立于团簇几何形状，直到团簇内的颗粒间距离超过颗粒直径的十倍。我们的模拟结果为基于纳米颗粒聚集的核磁共振传感器的设计提供了原则。(C)2008 Elsevier Inc.保留所有权利。
Clustering strongly affects the transverse (7,) relaxation induced by superparamagnetic nanopartictes in magnetic resonance experiments. In this study, we used Monte Carlo simulations to investigate systematically the relationship between T-2 values and the geometric parameters of nanoparticle clusters. We computed relaxation as a function of particle size, number of particles per cluster, interparticle distance, and cluster shape (compact vs. linear). We found that compact clusters induced relaxation equivalent to similarly sized single particles. For small particles, the shape and density of clusters had a significant effect on T-2. In contrast, for larger particles, T-2 relaxation was relatively independent of cluster geometry until interparticle distances within a cluster exceeded ten times the particle diameter. Results from our simulations suggest principles for the desgin of nanoparticle aggregation-based sensors for MRI. (c) 2008 Elsevier Inc. All rights reserved.