【作者】 邵君；

【导师】 高峰；

【作者基本信息】 上海交通大学 ， 化学工程， 2007， 硕士

【摘要】 随着纳米科技的兴起,量子点以其独特的光学性质在许多领域表现出潜在的应用价值,引起了人们浓厚的研究兴趣。由于其强于有机染料的荧光稳定性、激发光谱宽、发射光谱窄等优点,量子点作为标记物应用于免疫诊断和免疫分析中,逐渐取代传统的三大标记技术。因此探索用量子点标记建立快速简便的免疫学定量检测方法,有重要的研究意义。本文研究了pH值、缓冲溶液、温度、保存时间、氨基酸和蛋白质对量子点荧光性能的影响。采用连接剂将蛋白质与量子点偶联,通过酶联免疫竞争抑制法和斑点免疫渗滤法检测标记到量子点上蛋白质的活性。量子点和蛋白质连接后粒子分散性好,具有生物活性,可应用于免疫学检测。利用量子点的光学性能,建立了两种新颖的量子点标记的免疫分析方法,即量子点标记的免疫凝集分析法和量子点-纳米金荧光淬灭分析法,检测溶液中抗体或抗原的浓度。量子点标记的免疫凝集分析法是:采用量子点标记羊抗鼠IgG与鼠IgG免疫反应后形成网络结构,使量子点发生凝集,荧光信号减低,研究反应溶液中量子点荧光强度的变化,建立量子点标记的免疫凝集分析法,定量检测鼠IgG的浓度,最低检测极限为1.3nmol/L。量子点-纳米金荧光淬灭免疫分析法是采用量子点和纳米金粒子分别标记待测抗原相匹配的两种抗体,通过免疫反应形成抗原抗体复合物,使量子点与金粒子的距离靠近,量子点的能量转移给金粒子,引起量子点荧光淬灭,实验结果显示在570nm处信号淬灭的程度与体系中被更多还原

【Abstract】 Quantum dots (QDs), as a class of nanomaterials with many unique properties, have been explored potential applications in biomolecular detection. In compassion with organic dyes, QDs offer such advantages as better fluorescence stabilities, narrow emission bandwidths and broad absorption spectra. As a marker applied in immune diagnose and immunoassay, it is a trend that QDs are instead of three traditional labeled technologies. It is important to research the quantificational immune detection by QDs. Herein novel immunoassays were established by QDs for their fluorescence properties.Influences of pH, buffers, temperature, save time, amino acids and proteins on fluorescence of QDs were studied. QDs linked with proteins by EDC. Competitive inhibition ELISA method of magnetic particles-SA and CdTe-SA to Biotin-HRP and dot immuno-percolation were used to detect the biologic activity of proteins after labeling. The results proved that the CdTe-ptotein composite could be applied in immunoassays as it had good dispersivity and good bioactivity. Utilizing the fluorescence properties of QDs, two novel immunoassays were established, which were the aggregation-based immunoassay and fluorescence quenching immunoassay. These two methods were used to detect Immunoglobulin (IgG) and HBsAg.The aggregation-based immunoassay for detecting Mouse IgG using QDs has been developed by using two matched antibodies. The Goat anti-Mouse IgG (GMIgG) labelled quantum dots was mixed with MIgG. After the immunoreaction between GMIgG and MIgG, the quantum dots aggregated to form a network, which could quench the fluorescence of themselves in the reaction system. The more MIgG was, the bigger the network was, and the fluorescence intensity of quantum dots decreased linearly. The concentration of MIgG could be detected by the measurement of QDs fluorescence intensity at 567nm, and the limit detecting concentration was 1.3nmol/L.QDs-GNPs fluorescence quenching immunoassay was developed through detecting the concentration of Hepatitis B Surface Antigen (HBsAg) in serum. To demonstrate its更多还原