Effect of Hollow Structures on <i>T</i> ₁ and <i>T</i> ₂ Relaxivities and Their Application in Accurate Tumor Imaging

作者全名："Zeng, Jie; Huo, Linlin; Wang, Zhenyu; Sun, Xin; Guo, Yu; Li, Muyao; Tan, Mingya; Zhu, Shiqi; Fang, Jingqin; Zhao, Zhenghuan"

作者地址："[Zeng, Jie; Huo, Linlin; Li, Muyao; Tan, Mingya; Zhu, Shiqi; Zhao, Zhenghuan] Chongqing Med Univ, Coll Basic Med Sci, Chongqing 400016, Peoples R China; [Wang, Zhenyu] Univ Elect Sci & Technol China, Sch Phys, Chengdu 610054, Peoples R China; [Wang, Zhenyu] Univ Elect Sci & Technol China, State Key Lab Elect Thin Films & Integrated Devic, Chengdu 610054, Peoples R China; [Sun, Xin; Guo, Yu; Fang, Jingqin] Army Med Univ, Daping Hosp, Dept Radiol, Chongqing 400042, Peoples R China"

通信作者："Zhao, ZH (通讯作者)，Chongqing Med Univ, Coll Basic Med Sci, Chongqing 400016, Peoples R China."

来源：CHEMISTRY OF MATERIALS

ESI学科分类：MATERIALS SCIENCE

WOS号：WOS:001062619000001

JCR分区：Q1

影响因子：7.2

年份：2023

卷号：35

期号：18

开始页：7643

结束页：7654

文献类型：Article

关键词：　

摘要："Great progress in precisely controlling the structures of magnetic nanoparticles has been made to investigate structure-relaxivity relationships in recent years. However, the investigation of the influence of hollow structures with unique interior structures on the relaxation rate of magnetic nanoparticles is rare. Herein, we obtained a series of hollow manganese-doped iron oxide nanoparticles (MnIONs) with different void and dopant ratios through a controllable etch process and systemically investigated the influence of hollow structures on the T-1/T-2 relaxation rate. Due to the increased surface-to-volume (S/V) ratio, hollow MnIO nanoparticles (HMNs) show increased T-1 relaxivity compared to solid MnIONs. The T-1 relaxivities of HMNs with different void ratios are proportion to the number of exposed magnetic ions and electronic relaxation time value, which are determined by the S/V ratio and dopant level. More importantly, HMNs exhibit reduced saturated magnetization values with increased T-2 relaxivities compared to solid MnIONs. The elevated T-2 relaxivities of HMNs are attributed to the increased number of magnetic cores per unit volume and magnetic field inhomogeneity induced by hollow structures. These parameters are highly dependent on their void ratios, thus eventually determining their T-2 relaxivities. In vivo studies demonstrate that HMNs with relatively high T-1 or T-2 relaxivity show superior sensitivity in tumor detection to traditional T-1 or T-2 contrast agents. This work summarized the effects and mechanisms of hollow structures on the T-1 and T-2 relaxation rates of magnetic nanoparticles, providing examples in vivo for the design of excellent T-1 or T-2 contrast agents (CAs) for early cancer diagnosis."

基金机构：National Natural Science Foundation of China [81871421]; Chongqing High-level Personnel of Special Support Program [CQYC201905077]; Creative Research Group of CQ University [CXQT21017]; Program for Youth Innovation in Future Medicine; Chongqing Medical University [W0105]

基金资助正文："This work was supported by the National Natural Science Foundation of China (81971609 and 81871421), Chongqing High-level Personnel of Special Support Program (Youth Topnotch Talent CQYC201905077), Creative Research Group of CQ University (CXQT21017), and Program for Youth Innovation in Future Medicine, Chongqing Medical University (W0105)."