金基壳层材料的光学性质及负载pEGFP-C1质粒的研究

发布时间：2018-11-23 07:47

【摘要】：纳米技术的不断发展,多功能纳米材料在生物、医学领域备受人们的关注,特别是利用纳米材料的物化特性来研究生物体系的相互作用过程问题已成为目前的研究热点。然而纳米材料在生物医学的应用仍然面临许多挑战性问题。其中纳米材料与生物分子相互作用的机理仍没有全面的认识,如何用有效手段来确定它们的结合位点等问题成为人们研究的重点。一种介电质为核,贵金属为壳的复合纳米材料因其大的散射截面和良好生物相容性成为新的生物功能材料。基于金壳纳米材料与生物分子的复合物在光的照射下会产生高灵敏的表面增强拉曼光谱(SERS)。通过光谱可以判断生物分子与纳米材料的作用位点,同时该材料能够与生物分子复合后进入细胞,利用SERS进行体内示踪。所以金基壳层纳米材料将有助于研究其与生物分子的相互作用,可以广泛应用于生物标记、医学诊断和生物组织识别、以及药物释放、光热治疗等生物医学领域。本论文着重研究Au/Ag合金壳层材料的拉曼增强效应,并利用金基壳层材料研究其与质粒的作用机制问题,具体内容如下:1.通过改变金与银源的相对比例,制备粒径可控的以二氧化硅球为核,Au、Ag合金为壳的复合材料。以Au/Ag合金壳层材料为基底进行对巯基苯胺的拉曼检测。通过分析拉曼光谱,发现Au/Ag合金壳层复合材料要比纯金壳层材料的SERS活性强,是一种生物相容性好、活性高的SERS基底材料。2.为了使金壳复合纳米材料能偶联质粒,分别利用高分子聚合物PEI、PEG修饰金壳层纳米材料的表面。通过研究反应条件对金壳层纳米材料表面修饰的影响,发现反应环境的p H值大于9有利于金壳层纳米材料的表面修饰。最适合负载DNA的PEI-Au复合材料与质粒p EGFP-C1相互作用后,通过凝胶阻滞实验,获得二者的最佳结合比例,实现负载质粒。
[Abstract]:With the development of nanotechnology, multifunctional nanomaterials have attracted much attention in the field of biology and medicine. Especially, it has become a hot topic to study the interaction process of biological systems by using the physicochemical properties of nanomaterials. However, the application of nanomaterials in biomedicine still faces many challenges. The mechanism of interaction between nanomaterials and biomolecules has not been fully understood. How to determine their binding sites by effective means has become the focus of research. A composite nanomaterial with dielectric material as core and precious metal as shell has become a new biofunctional material because of its large scattering cross section and good biocompatibility. The complex based on gold shell nanomaterials and biomolecules can produce highly sensitive surface-enhanced Raman spectroscopy (SERS).) under light irradiation. The interaction sites between biomolecules and nanomaterials can be determined by spectrum. At the same time, the biomolecules can be combined with biomolecules to enter cells and trace in vivo by using SERS. Therefore, gold based shell nanomaterials will be helpful to study their interactions with biomolecules and can be widely used in biomedical fields such as biomarkers, medical diagnostics and biologic tissue recognition, drug release, photothermal therapy, and so on. In this paper, the Raman enhancement effect of Au/Ag alloy shell material is studied, and the mechanism of its interaction with plasmids is studied by using gold base shell material. The main contents are as follows: 1. By changing the relative ratio of gold and silver, a composite material with controlled particle size of silica ball as core and Au,Ag alloy as shell was prepared. The Au/Ag alloy shell material was used as the substrate for the Raman detection of p-mercaptophenylamine. By analyzing Raman spectra, it is found that Au/Ag alloy shell composite has higher SERS activity than pure gold shell material, and is a kind of SERS substrate with good biocompatibility and high activity. 2. In order to make the gold-shell composite nano-materials can be coupled with plasmids, the surface of gold-shell nanomaterials was modified by polymeric polymer PEI,PEG. By studying the effect of reaction conditions on the surface modification of gold shell nanomaterials, it is found that the pH value of the reaction environment is greater than 9 in favor of the surface modification of gold shell nanomaterials. After interaction between PEI-Au composite and plasmid p EGFP-C1 which is most suitable for loading DNA, the best proportion of the two was obtained by gel block experiment, and the loading plasmid was realized.
【学位授予单位】：东北师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1

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