Scholarlink

<p>Manganese ferrite nanoparticles have attracted considerable interest in the field of magnetic resonance imaging as contrast agents due to their exceptional magnetic properties. Structural features, such as size polydispersity and random cation distribution, can vary simultaneously during the preparation of these nanoparticles, which significantly influences their magnetic properties and, consequently, their transverse relaxivity. The theoretical prediction of this influence therefore deserves special attention. In this context, molecular dynamics and density functional theory calculations were extensively used. Our simulation results showed that the smaller the nanoparticle size, the higher the surface area to volume ratio. However, the variation of this ratio leads to heterogeneity of the crystal lattice constant across the nanoparticle. This, combined with the random distribution of cations, leads to variations in magnetization, and consequently, in transverse relaxivity. More interestingly, transverse relaxivity was found to increase with size, and beyond 10&#xa0;nm, a notable dependence on cation distribution appeared. The lower the degree of inversion, the higher the relaxivity. Such a critical size is actually smaller than those of conventional ferrite-based contrast agents. Our study therefore has the merit of guiding the experimental operator in order to better predict the evolution of relaxivity as a function of the size and distribution of cations, which opens the way to better control of the effectiveness of ferrite manganese-based contrast agents.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Prediction of Transverse Relaxivity of MnFe2O4 Nanoparticles as a Function of Their Sizes and Cation Distribution

  • 期刊论文

  • 发表日期：

    2025年11月20日

查看全文
  • Mohammed Benaissa,
  • Ahmed Al Shami,
  • Hicham Labrim

摘要

Manganese ferrite nanoparticles have attracted considerable interest in the field of magnetic resonance imaging as contrast agents due to their exceptional magnetic properties. Structural features, such as size polydispersity and random cation distribution, can vary simultaneously during the preparation of these nanoparticles, which significantly influences their magnetic properties and, consequently, their transverse relaxivity. The theoretical prediction of this influence therefore deserves special attention. In this context, molecular dynamics and density functional theory calculations were extensively used. Our simulation results showed that the smaller the nanoparticle size, the higher the surface area to volume ratio. However, the variation of this ratio leads to heterogeneity of the crystal lattice constant across the nanoparticle. This, combined with the random distribution of cations, leads to variations in magnetization, and consequently, in transverse relaxivity. More interestingly, transverse relaxivity was found to increase with size, and beyond 10 nm, a notable dependence on cation distribution appeared. The lower the degree of inversion, the higher the relaxivity. Such a critical size is actually smaller than those of conventional ferrite-based contrast agents. Our study therefore has the merit of guiding the experimental operator in order to better predict the evolution of relaxivity as a function of the size and distribution of cations, which opens the way to better control of the effectiveness of ferrite manganese-based contrast agents.