双模态磁共振/近红外活体影像纳米探针的制备及其应用研究

项目名称： 双模态磁共振/近红外活体影像纳米探针的制备及其应用研究

项目编号： No.21301187

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 董博华

作者单位： 中国海洋大学

项目金额： 25万元

中文摘要： 构建具有光磁双功能复合的纳米探针，同时实现荧光和磁共振双模态成像，在生物医学领域展现出诱人的研究价值和应用潜力。目前的光磁复合探针主要局限于磁性纳米粒子与可见光荧光发射的Cd基半导体量子点的复合，然而这些光磁复合结构有其局限性和不足：纳米复合结构中的量子点往往含有重金属Cd，生物相容性差；由于发光窗口的限制（400-700nm），在生物活体内光散射和吸收较大，一般无法实现生物活体组织的高灵敏度成像。本课题选择具有较高荧光效率和生物相容性的新型近红外Ag2Se量子点作为光学探针，其1300nm的近红外荧光由于较低的光吸收和散射, 可以实现最大穿透深度的活体荧光成像。然后将其进一步与磁性纳米粒子复合，探索新的合成策略，构建具有磁共振/近红外双模态的活体影像纳米探针，从而为生物活体组织的高分辨率和高灵敏度成像提供新的思路。本项目发展的合成策略，也将为制备其他多功能纳米材料奠定基础。

中文关键词： 量子点；多功能纳米材料；可控合成；纳米复合结构；近红外二区

英文摘要： The fluorescent magnetic nanoprobes fabricated by combining magnetic nanoparticle with quantum dot (QDs) can obtain dual-modal imaging (including magnetic resonance imaging (MRI) and fluorescent imaging ) showing their intriguing potentials in the field of biomedicine. Up to now, the optical reagents of fluorescent-magnetic nanoprobes has been mainly focused on the Cd-based QDs. The intrinsic heavy metal Cd components of QDs greatly restrict their application in in vivo. Another problem in these nanoprobes is that the fluorescent window of Cd-based QDs as optical regent exists at wavelength between 400 nm and 700nm, which is not suitable for in vivo imaging with high sensitivity. In this program, we plan to synthesize highly photoluminescent and decently biocompatible Ag2Se QDs with near-infrared emission in the second window (NIR-II, 1000-1400 nm), which offer deeper tissue penetration and negligible auto-fluorescence due to the lower photon absorption and tissue scattering, and then used Ag2Se NIR-II QDs with emission centered at 1300 nm as optical reagents to fabricate MRI/NIR-II fluorescent nanoprobe by a facile and general strategy. The obtained MRI/NIR-II dual-modal nanoprobe will provide a new route for in vivo imaging with high resolution and sensitivity. The developed strategy will also provide opportun

英文关键词： Quantum Dots；Multiple-functional Nanomaterials；Controlled Synthesis；Nanocomposite structure；Second Near-infrared