• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Advanced Functional Materials >Gd~(3+)-lon-Doped Upconversion Nanoprobes: Relaxivity Mechanism Probing and Sensitivity Optimization
【24h】

Gd~(3+)-lon-Doped Upconversion Nanoprobes: Relaxivity Mechanism Probing and Sensitivity Optimization

机译：掺杂Gd〜（3 +）-lon的上转换纳米探针：弛豫机理探测和灵敏度优化

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Paramagnetic gadolinium (Gd-lll)-ion-doped upconversion nanoparticles (UCNPs) are attractive optical-magnetic molecule imaging probes and are a highly promising nanoplatform for future theranostic nanomedicine design. However, the related relaxivity mechanism of this contrast agent is still not well understood and no significant breakthrough in relaxivity enhancement has been achieved. Here, the origin and optimization of both the longitudinal (r_1) and transverse (r_2) relaxivities are investigated using models of water soluble core@shell structured Gd~(3+)-doped UCNPs. The longitudinal relaxivity enhancement of the nanoprobe is demonstrated to be co-contributed by inner-and outer-sphere mechanisms for ligand-free probes, and mainly by outer-sphere mechanism for silica-shielded probes. The origin of the transverse relaxivity is inferred to be mainly from an outer-sphere mechanism regardless of surface-coating, but with the r_2 values highly related to the surface-state. Key factors that influence the observed relaxivities and r_2/r_1 ratios are investigated in detail and found to be dependent on the thickness of the NaGdF_4 interlayer and the related surface modifications. A two orders of magnitude (105-fold) enhancement in r_1 relaxivity and 18-fold smaller r_2/r_1 ratio compared to the first reported values are achieved, providing a new perspective for magnetic resonance (MR) sensitivity optimization and multimo-dality biological imaging using Gd~(3+)-doped UCNPs.
机译：顺磁性ado（Gd-III）离子掺杂的上转换纳米颗粒（UCNPs）是有吸引力的光磁分子成像探针，并且是用于未来治疗学纳米医学设计的高度有前途的纳米平台。然而，该造影剂的相关弛豫机理仍未得到很好的理解，并且在弛豫度增强方面没有取得重大突破。在此，使用水溶性核@壳结构的Gd〜（3+）掺杂UCNPs模型研究了纵向（r_1）和横向（r_2）弛豫的起源和优化。纳米探针的纵向弛豫度增强被证明是由无配体探针的内球和外球机制共同贡献的，而对于二氧化硅屏蔽探针则主要由外球机制共同贡献。横向弛豫的起源主要是由外层机理引起的，与表面涂层无关，但r_2值与表面状态高度相关。详细研究了影响观察到的弛豫度和r_2 / r_1比率的关键因素，发现这些因素取决于NaGdF_4中间层的厚度和相关的表面改性。与最初报道的值相比，r_1弛豫性提高了两个数量级（105倍），r_2 / r_1比减小了18倍，为磁共振（MR）灵敏度优化和多态生物成像提供了新的视角使用Gd〜（3+）掺杂的UCNP。

著录项

  • 来源
    《Advanced Functional Materials》 |2013年第3期|298-307|共10页
  • 作者

    Feng Chen; Wenbo Bu; Shengjian Zhang; Jianan Liu; Wenpei Fan; Liangping Zhou; Weijun Peng; Jianlin Shi;

  • 作者单位

    Group of Mesoporous and Low-Dimensional Nano-materials, State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai, 200050, People's Republic of China;

    Group of Mesoporous and Low-Dimensional Nano-materials, State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai, 200050, People's Republic of China;

    Department of Radiology Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University Shanghai 200032, China;

    Group of Mesoporous and Low-Dimensional Nano-materials, State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai, 200050, People's Republic of China;

    Group of Mesoporous and Low-Dimensional Nano-materials, State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai, 200050, People's Republic of China;

    Department of Radiology Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University Shanghai 200032, China;

    Department of Radiology Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University Shanghai 200032, China;

    Group of Mesoporous and Low-Dimensional Nano-materials, State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai, 200050, People's Republic of China;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号