基于多孔银基底的固相微萃取与表面增强拉曼联用技术及其在快速分析检测中的应用

发布时间：2018-01-14 08:00

本文关键词：基于多孔银基底的固相微萃取与表面增强拉曼联用技术及其在快速分析检测中的应用　出处：《山东大学》2017年博士论文　论文类型：学位论文

【摘要】：表面增强拉曼光谱(Surface Enhanced Raman Spectroscopy,SERS)是一种高灵敏分析技术,通过纳米结构的电磁和化学效应可以有效增强光谱强度,提供吸附分子的详细振动信息。SERS已经广泛的应用于环境监测、食品分析、材料科学、生物医学检验等领域中。SERS基底的制备技术是影响SERS技术实用化的关键科学问题,例如热点的构建,基底的稳定性、均匀性和耐候性等。随着纳米技术的发展,基底的制备方法也越来越多样化,如何获得兼具增强能力和均匀稳定性的基底依然是制约其应用的一个关键性问题。固相微萃取(Solid Phase Microextraction,SPME)是一种高效、快速的样品前处理技术。其原理是依据分析物在固相微萃取涂层和样品基质之间的分配平衡,将分析物从样品基质中富集到固相萃取涂层上。固相微萃取已经广泛应用于环境分析、食品分析、生物分析等领域。近年来,固相微萃取与各种分析仪器的联用技术也在飞速发展,极大拓展了其应用范围。本文发展了一种具有SERS活性的多孔银纳米结构固相微萃取基底,并通过Galvanization-Freec沉积反应在多孔银表面形成超薄金膜,提高基底的稳定性和均匀性。采用各种物理化学方法对基底进行表征,结果表明该多孔银基底兼具良好的SERS活性和SPME萃取性能。具体如下:1利用电化学法原位合成多孔银纳米结构,采用X射线衍射(XRD),扫描电子显微镜(SEM),原子力显微镜(AFM)和接触角测试对结构和性能进行了表征。多孔银基底是由纳米颗粒及其堆积孔构成,表面具有疏水性,兼具良好的SERS活性和吸附萃取性能。利用此基底,建立了针对有机锡化合物的SPME-SERS联用分析方法。根据SERS的分子指纹峰,实现对三甲基氯化锡,二丁基二氯化锡,三丁基氯化锡,三苯基氯化锡和四苯基氯化锡快速分析识别,检测限达到ppb水平。研究了萃取过程的吸附热力学和动力学过程,并采用主成分分析(principal component analysis,PCA)对有机锡的分子指纹峰进行统计学分类,最后通过ICP-MS对以上方法进行了验证,实现了有机锡化合物的现场快速分析检测。2在此基础上,通过引入卤素离子提高Ag+电极电位,抑制Au3+/Ag之间的Galvanic replacement反应,同时利用抗坏血酸作为还原剂和稳定剂在多孔银表面形成超薄的金沉积膜,采用AFM,XPS,SEM和元素Mapping进行了表征。然后以巯基苯胺作为探针,考察了 porousAg@Au基底的热稳定性和均匀性,利用热红外成像仪研究了基底的实时导热情况。采用SPME-SERS联用方法对水产品中违禁药物呋喃西林及其代谢物(氨基脲)的进行了快速分析,检出限达到ppb水平。3采用氨基/硝基苯硫酚作为探针修饰porousAg@AuSERS基底,根据SERS光谱研究不同表面氧化态的配体与蛋白质分子的相互作用。合成了金纳米颗粒作为模型,利用毛细管电泳分离纳米颗粒/蛋白质分子复合物,计算解离常数和协同常数。同时,采用分子对接方法对particles-proteins模型的空间结合点位及作用力进行了理论计算,从分子角度为颗粒的生物毒性和代谢过程研究提供理论依据。
[Abstract]:Surface enhanced Raman spectroscopy (Surface Enhanced Raman Spectroscopy, SERS) is a high sensitive analytical technique, the electromagnetic and chemical effects of nano structure can effectively enhance the spectral intensity, provide application with vibration information of.SERS adsorption molecules have been widely in environmental monitoring, food analysis, material science and technology in the field of biomedical test preparation.SERS substrate is a key scientific problem to influence the practical use of SERS technology, such as hot construction, basal stability, uniformity and weathering resistance. With the development of nanotechnology, the substrate preparation method is becoming more and more diversified, how to obtain both enhanced basal ability and uniformity and stability is still restricting the application of a key problems. Solid phase microextraction (Solid Phase, Microextraction, SPME) is an efficient, fast sample pretreatment technique. Its principle is based on the analysis. The distribution balance between SPME coating and the sample matrix, the analyte from the sample matrix to the enrichment of solid phase extraction coatings. Solid phase microextraction has been widely used in environmental analysis, food analysis, biological analysis and other fields. In recent years, solid phase microextraction and various analytical instruments combined with technology is developing rapidly. Has greatly expanded its scope of application. This paper develops a model of SERS active porous silver nano structure of solid phase micro extraction and substrate deposited by Galvanization-Freec reaction form a thin gold film on porous silver surface, improve the stability and uniformity of the substrate by various physical and chemical methods were used to characterize the substrate. The results show that the porous silver the basal activity of SERS and SPME had good extraction performance. The details are as follows: 1 using electrochemical method for in situ synthesis of porous silver nanostructures by X ray diffraction (XRD), scanning electron microscope Micro mirror (SEM), atomic force microscopy (AFM) and contact angle measurements on the structure and properties were characterized. The porous silver substrate is composed of nano particles and the accumulation of holes, with hydrophobic surface, good adsorption performance. The activity of SERS and extraction using this substrate, SPME-SERS was established for organic tin compounds the analysis method combined with molecular fingerprint. According to the peak of SERS, to achieve the three methyl tin chloride, butyl two two three tin chloride, stannous chloride, rapid analysis identified three fentin chloride and four phenyl tin chloride, the detection limit can reach ppb level. The adsorption kinetics and thermodynamics of the extraction process, and the main component analysis (principal component analysis, PCA) molecular fingerprint peaks of organic tin were classified, and finally through the ICP-MS of the method was verified, the spot of organotin compounds rapid detection and analysis of the.2 in On this basis, through the introduction of halogen ions increase Ag+ electrode potential, inhibition of Galvanic replacement reaction between Au3+/Ag, while using ascorbic acid as the gold deposited film, reducing agent and stabilizer in the formation of thin porous silver surface by AFM, XPS, SEM and Mapping elements were characterized. Then with mercapto aniline were investigated as probe. The stability of the porousAg@Au substrate and the uniformity of heat transfer on the substrate by using real-time thermal infrared imager. Using SPME-SERS coupling method of illicit drugs in aquatic products of nitrofurazone and its metabolite (amino urea) was used for rapid analysis, the detection limit of ppb.3 level reached by the amino modified porousAg@AuSERS / nitrobenzene Thiophenol as the probe substrate, according to the interaction of the ligand SERS spectroscopic studies on the oxidation of different surface states and protein molecules. Gold nanoparticles were synthesized as model, the use of hair The separation of nanoparticle / protein molecular complex capillary electrophoresis, calculation of dissociation constants and cooperativity constants. At the same time, using the molecular docking method to the particles-proteins model combined with the space position and force are calculated from the molecular point of view for the biological toxicity of particles and metabolic process research and provide a theoretical basis.

【学位授予单位】：山东大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O657.37;O658.2

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