近红外荧光磁性多功能纳米粒子的精密合成

Near-infrared (NIR) with the wavelength in the range between 700 and 900 nm, also known as "spectra window", is an uncovered region of self-emission fluorescence for biosomes. Therefore, a clear fluorescece imaging 5-12 cm deep into the tissue can be observed within this range avoiding the interfere arising from the organsims (background) itself. By combination with the technique of magnetic resonance imaging (MRI), which owns high spatial resolution, guaranteed by magnetic nanoparticles, we can obtain much more valuable information for both diagnosis and treatment through simultaneous application of such two means. We in turn plan to empoly "living" radical polymerization (ATRP and RAFT) to modify the silica coated ferriferrous oxide (Fe3O4@SiO2) with controlled (co)polymer layers which possess propertis of NIR fluorescence and hydrophilicity. Apart from that, some specific targeting molecules can also be fixed on the nanoparticles through certain end-group reactions; accordingly a facile synthetic strategy to prepare multifunctional nanoparticles with characteristics of specific targeting, NIR fluorescence, magnetism and good dispersibility in aqueous media can be established. The effects of numerous factors including the size of the magnetic core, the thickness of the silica shell, types of the NIR monomer as well as the thickness of the grafted (co)polymers on multifunctional nanoparticles will be studied in this project. Accoding to the above mentioned method, we will provide novel multifunctional inorgnic/orgnic hybrid nanomaterials with core/shell structure bearing NIR fluorescence, magnetism and specific targeted groups for in vivo imaging based on optimum experimental conditions.

近红外区（700-900 nm）是生物体的荧光空白区，利用这个空白区可以避开生物体自身荧光发射所造成的背景干扰获得处于生物体5-12 cm深处的在体分子荧光影像，结合磁性纳米粒子的三维磁共振成像技术，借助解剖学和荧光分子的同时定位得到更多有用的诊断和治疗信息。本项目旨在采用活性自由基聚合（ATRP和RAFT）方法，把具有近红外荧光性能和水溶性单体可控接枝到二氧化硅层保护的磁性四氧化三铁纳米粒子上，同时通过基团反应把靶向基团固定于纳米粒子上，建立集靶向、近红外荧光和磁性能于一体并可稳定分散在水性环境中的多功能纳米粒子精密合成方法。掌握磁性纳米粒子大小、包裹的二氧化硅保护层厚度、近红外荧光单体种类、接枝的荧光聚合物及亲水聚合物层厚度以及聚合物结构等对多功能纳米粒子荧光和磁性能的影响规律，同时为在体生物成像技术提供一种集近红外荧光、磁性和靶向性能于一体的核壳结构的多功能无机/有机杂化纳米新材料。

近红外区是生物体的荧光空白区，利用这个空白区可以避开生物体自身荧光发射所造成的背景干扰获得处于生物体5-12 cm 深处的在体分子荧光影像，结合磁性纳米粒子的三维磁共振成像技术，借助解剖学和荧光分子的同时定位将可得到更多有用的诊断和治疗信息。因此可控合成集近红外荧光、磁性能以及具有光热和光动治疗等癌症治疗效果相结合于一体的多功能纳米粒子是充分发挥该技术优势的关键。本项目利用“活性”自由基聚合（ATRP 和RAFT 聚合）方法具有的超强的分子设计能力的特点，构建了集近红外荧光、磁性能、亲水性能、癌症诊疗性能以及环境刺激响应性能于一体的多功能纳米粒子精密合成方法。该方法可根据实际需要选择性地设计集成1＋X 功能（1 代表近红外荧光；X 代表磁性能，亲水性能，抗癌药物装载、光热以及光动等癌症诊疗性能以及环境刺激响应性能中的一种、几种或者全部）为活体多维快速诊断以及原位治疗无（低）毒性多功能纳米材料提供一种新的可控合成方法。在项目基金的资助下，在Nanoscale, ACS Applied Materials & Interfaces, Journal of Materials Chemistry B 以及 Polymer Chemistry等主流杂志上发表SCI源期刊研究论文7篇，获得授权（在审）中国发明专利4 项，参加国内学术会议1 人次，参加国际学术会议1人次，完成博士毕业论文1 篇，硕士毕业论文2 篇，在读博士论文1篇，顺利完成项目的预期目标。