Ag纳米粒子表面隔离层对聚合物荧光的增强效应研究

发布时间：2018-03-08 20:02

本文选题：Ag纳米粒子　切入点：Ag/BSA核壳结构纳米粒子　出处：《广东工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：表面荧光增强效应被广泛地应用于生物大分子检测、材料分析和环境检测等各个领域,因此制备具有良好的表面荧光增强效应的基体成为了近年来的热门研究方向。本论文以硝酸银为氧化剂,柠檬酸钠为还原剂,采用氧化还原法制备了球形银纳米粒子,采用扫描电子显微镜分析其形貌及单分散性。在Ag纳米粒子基础上采用沉积自组装法合成了Ag/BSA核壳结构纳米粒子,结合SEM、透射电子显微镜和X射线衍射对其进行表征分析。分别研究了Ag纳米粒子和Ag/BSA核壳结构纳米粒子对聚苯乙烯的荧光增强效应并进行比较分析。实验结果表明,最佳的反应时间为5min,制备的Ag纳米粒子粒径处于50-65nm,加入不同量的BSA得到了有效粒径为80.8nm和100.6mnm两种尺寸的Ag/BSA核壳结构纳米粒子。Ag纳米粒子和Ag/BSA核壳结构纳米粒子都呈现球状,单分散性良好,而且BSA有效地包覆在Ag纳米粒子的外层。紫外吸收光谱结果表明,BSA的引入导致了Ag纳米粒子表面的电子密度发生变化以及纳米颗粒粒径增大,从而引起了等离子共振吸收峰的红移现象。荧光发射光谱结果表明,Ag纳米粒子能使PS得荧光强度有所增强,而Ag/BSA核壳结构纳米粒子使得PS的荧光强度从100增强到6000,说明了BSA隔离层对位于Ag表面附近的PS分子的荧光强度有显著的增强效应。
[Abstract]:Surface fluorescence enhancement has been widely used in many fields, such as biomolecules detection, material analysis and environmental detection, etc. In this paper, silver nanoparticles were prepared by redox method with silver nitrate as oxidant and sodium citrate as reducing agent. The morphology and monodispersity of Ag nanoparticles were analyzed by scanning electron microscope (SEM). Ag/BSA core-shell structure nanoparticles were synthesized by deposition self-assembly method on the basis of Ag nanoparticles. The fluorescence enhancement effects of Ag nanoparticles and Ag/BSA core-shell structure nanoparticles on polystyrene were studied and compared. The best reaction time is 5 min, the particle size of Ag nanoparticles is 50-65 nm, and the effective size of Ag/BSA core-shell structure nanoparticles. Ag nanoparticles and Ag/BSA core-shell structure nanoparticles are spherical by adding different amount of BSA, the effective particle sizes are 80.8nm and 100.6mnm, respectively. BSA was effectively coated on the outer layer of Ag nanoparticles. The UV absorption spectra showed that the introduction of BSA resulted in the change of electron density on the surface of Ag nanoparticles and the increase of particle size. As a result, the red shift of the plasmon resonance absorption peak was induced. The fluorescence emission spectra showed that the fluorescence intensity of PS was enhanced by Ag nanoparticles. However, the fluorescence intensity of PS increased from 100 to 6000 by Ag/BSA core-shell structure nanoparticles, which indicates that the BSA isolation layer has a significant enhancement effect on the fluorescence intensity of PS molecules located near the Ag surface.
【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O614.122;TB383.1

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