金纳米粒子组装制造及组装体电磁场效应研究

Nowadays, the organization or assembly of nanoparticles is becoming an important research topic in the field of Nanofabrication. When two metal nanoparticles are placed very close together, near field coupling may occur between their surface plasma due to the transfer and confinement of electromagnetic energy, which greatly enhances the local electromagnetic field between two adjacent nanoparticles. The collective properties exhibit great potential applications, especially in trace detection. This application is mainly based on our groups’ research of “the basic research subject of manufacturing nano gold array based on DNA self-assembly”, and hope get in-depth research in the field. This project mainly studies on rational design of Au nanorods and Au nanospheres assemblies and the application on trace detection of melamine in milk. First, we designe a universal strategy to design assemblies by introducing a third assembly unit-AuNRs to assemble with AuNSs through electrostatic interaction; Second, we explain the development law between the structure of assemblies and their properties. Third, we demonstrate highly sensitive SERS detection of analyte based on fabrication of AuNSs and AuNRs assemblies, using the detection of melamine as an example. Finally, this research tries to provide science guidance for the fabrication of novel noble metal assemblies and further enriches the theory and applications of nanofabrication.

纳米粒子组装在纳米制造领域越来越受到研究者的关注。当两个金属纳米粒子非常靠近时，两个粒子的连接点会发生耦合效应，导致连接点处的电磁场显著增强。组装后的这些性质具有巨大的潜在应用前景，尤其用于检测微量信号。本项目主要是在本课题组“基于DNA自组装制造纳米金阵列的基础研究”的研究基础上，进一步深入开展的研究。主要研究金纳米球（AuNSs）中引入第三个组装单元金纳米棒（AuNRs）作为诱发剂，通过静电作用使其形成组装体；阐明组装体的构效关系；以三聚氰胺为例，利用AuNSs-AuNRs组装体实现对检测物的高灵敏度表面增强拉曼散射（SERS）光谱信号的检测；研究结果可为合理设计和制造新型贵金属纳米组装体提供科学依据，并拓展纳米材料的制造理论基础及应用范围。

本项目成功合成了多种不同形态、尺寸可控的金纳米粒子并对其形貌进行了表征；通过引入第三个组装单元纳米棒（AuNRs）设计金纳米粒子组装体，发展了一种新型通用纳米组装体的设计方法；以三聚氰胺为例，利用组装体实现了对检测物的高灵敏度表面增强拉曼散射（SERS）光谱信号的检测（检测限：1 ppb）, 该方法预处理简单，检测限低，重现性好，适用于日常生活牛奶中三聚氰胺的检测；构建了载药壳聚糖-金纳米棒组装体，体外细胞实验评价结果显示，并肩排列的纳米棒在肿瘤治疗中效果良好，为肿瘤治疗研究开拓了新的治疗途径——化疗-光热疗一体化；对大分子分子量（如聚乙二醇分子量1000-12000）、金属离子（如：汞离子，检测限0.1 nM）、小分子(如：茶碱，检测限0.05 μM)进行了高特异性和灵敏性的检测；合成了丝素蛋白单组分微囊，再用功能化金纳米棒进行修饰，杂化微囊具有很强的拉曼增强性质，在诊疗一体化或光热疗-化疗联合治疗方面具有应用潜力；此外，制备了多种蛋白-纳米金、多糖-纳米银杂化微结构，在细胞-材料相互作用、药物传递等方面具有重要研究意义。以上研究为合理设计和制造新型贵金属纳米组装体提供了科学依据，同时丰富了纳米制造的理论基础及应用范围。