DNA编码组装高灵敏的纳米哑铃SERS标记免疫探针的研究

项目名称： DNA编码组装高灵敏的纳米哑铃SERS标记免疫探针的研究

项目编号： No.21305142

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： 刘洪林

作者单位： 中国科学院合肥物质科学研究院

项目金额： 25万元

中文摘要： 基于Raman标签的表面增强拉曼光谱(SERS)，因其独特的指纹特征、超灵敏、多重检测等优势，成为标记免疫检测领域的研究重点之一。SERS标记免疫检测面临的核心科学问题之一是：高产率构筑高增强活性纳米结构的同时，如何可控地定位Raman标签并稳定地修饰抗体分子。本项目以此为目标牵引，采用DNA编码组装策略，解决Raman标签定位的可控性问题和抗体分子修饰的稳定性问题：①组装间隙距离固定的Au纳米颗粒二聚体（纳米哑铃），并在其表面包覆不同厚度的Ag壳，实现二聚体的间隙大小在3 nm范围内的可调可控；②利用DNA编码组装，重点发展在哑铃间隙内可控标记Raman标签以及在哑铃表面稳定修饰抗体分子的方法。使得每个纳米粒子具备一个标记有Raman标签的热点，而且表面稳定修饰一种抗体分子，获得高灵敏、高稳定的SERS标记免疫探针。项目预期成果将为SERS标记免疫探针的设计与调控提供新的思路。

中文关键词： 表面增强拉曼；自组装；热点；等离子体共振；液态界面

英文摘要： Surface enhanced Raman scattering (SERS) tags has been gradually applied in the field of protein detection because of its unique fingerprint characteristics, ultra-sensitivity, and the capability of multiple detection. In fact, the occurrence of distributed hot spots on SERS-active nanostructures has great randomness, leading to a wide distribution of enhancement factor values. Generally, SERS-based immunoassay faces an essential problem with structural reproducibility, as particle structure and interparticle distance can markedly affect Raman signals. Hence, high-yield assembling SERS-active nanoparticles into well-defined and reproducible hot SERS nanostructures, and synchronously marking the SERS tags and modifying specific molecule on individual SERS-active nanostructure would be greatly beneficial. In this project, based on a DNA-programmed synthetic strategy and a subsequent magnetic-particle-based separation method, 1) gold nanoparticles (Au NPs) were assembled into a dimeric structure, then Ag shells were formed on the surface of the dimeric Au NPs, and the Ag shell thickness was controlled on the nanometre scale to generate gap-engineerable, DNA-embedded nanodumbbells; 2) Importantly, taking advantage of the DNA-programmed assembly process, we will focus on the development of controllably marking the SE

英文关键词： surface-enhanced Raman；self-assembly；hotspot；plasma resonance；liquid-state interfacial