基于生物放大技术与新型结构纳米贵金属表面增强拉曼免疫分析新方法研究

项目名称： 基于生物放大技术与新型结构纳米贵金属表面增强拉曼免疫分析新方法研究

项目编号： No.21475097

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 高分子科学

项目作者： 林大杰

作者单位： 温州大学

项目金额： 80万元

中文摘要： 高灵敏检测癌症蛋白的免疫分析在疾病诊治、生物医药研究等领域至关重要。表面增强拉曼散射(SERS)免疫分析法具有灵敏度高、抗干扰能力强等优点，为蛋白的多组分超灵敏检测提供可能。通常，SERS免疫分析的灵敏度主要来自于纳米金对拉曼活性分子的SERS增强。存在纳米金粒径小，SERS增强弱，粒径大，探针不稳定的矛盾。本项目从构建高灵敏SERS免疫分析方法的特点出发，从SERS纳米探针、免疫传感界面及DNA生物放大三方面出发，拟可控合成结构新型的纳米材料，考察其形貌、尺寸、表面粗糙度对SERS信号的影响，制备出SERS高响应的纳米探针；利用LB组装技术，通过调节界面理化性质和改变抗体固定方法，构建超低背景噪音的SERS界面，结合DNA的生物放大技术，如滚环扩增、表面酶促聚合、核酸剪切酶放大等，对SERS探针进行有序组装，实现信号的多重放大，建立对肿瘤蛋白低丰度的检测方法，为临床诊断提供潜在应用。

中文关键词： 免疫分析；表面增强拉曼光谱；信号放大；DNA；肿瘤标志物

英文摘要： Highly sensitive determination of cancer biomarkers is critical to many areas, such as disease diagnosis and biomedical research. Surface-enhanced Raman scattering (SERS) immunoassay has the highly sensitive and multiplexing detection capability due to its narrow-band Raman spectral signature and its wide excitation wavelength. In general, the sensitivity of SERS immunoassay is attributed to the SERS effect of the molecules absorbed on the metal nanoparticle. It is well known that the response ability of the SERS is critically related to the size of the gold nanoparticles.Bigger gold nanoparticle s will result in greater SERS signals. But their stability may decrease significantly with the increasing sizes when they are functinalaized with Raman reporters.Fortunately,the surface enhancement effect can be remarkable generated by the assemlby of metal nanoparticle.DNA biological amplification is great suit to assembly for metal nanoparticle though biotin-streptavidin.In view of the characteristic of highly sensitive SERS immunoassay, this project proposes some novel strategy for protein by some novel SERS highly enhanced nanoprobes, the surface of the immunosensor and DNA biological amplification. Firstly, we intend to controlled synthesis some novel nanomaterials , investigate the relationship between SERS enhancement with morphology, size and surface roughness, clarify SERS enhancement mechanism, and prepare high SERS probes. Secondly, we intend to construction the surface of SERS immunosensor using LB technologies. The low background noise of SERS immunosensor'surface will be obtain though adjusting the physical and chemical properties and antibody immobilization methods. Finally, combining with DNA biological amplification technologies, such as rolling circle amplification, Surface-initiated enzymatic polymerization, and exonuclease III-aided DNA recycling amplification, some ultrasensitive SERS immunoassay methods for ultra-low abundance cancer biomarkers will be developed. The proposed system will be shown great promise for clinical application,and open a new avenue for sensitive immunoassay and other biochemical anlaysis based on SERS.

英文关键词： Immunoassay;Surface-enchanced Raman scattering;Signal amplification;DNA;Cancer biomarker