银纳米线膜试纸条与表面增强拉曼光谱联立用于快速现场检测

发布时间：2018-11-25 14:34

【摘要】：对日常生活中环境污染物中有效成分的评定至关重要,这与环境发展和人类的健康都紧密相关。所谓有效成分,就是可以被溶解或易于被萃取的物质部分,被认为是与有机体的生物累积、生物吸附和生物转换关联最深的部分。对于环境污染物有效成分进行快速现场分析,可以在短时间内完成违规物的初步筛选,实现高效监测过程。在检测前进行的分离纯化及富集过程对其后的检测影响很大,这也使得发展简便省时的样品前处理手段十分必要。贵金属基底可与巯基或氨基等官能团形成化学键作用,被基底直接吸附而完成对含硫/氮物质的样品分离和富集。贵金属表面也可利用化学键自组装形成修饰层,例如金、银和铜均可结合硫醇分子,由于硫醇的烷基链端聚集形成憎水区域而将各自表面由原本的亲水性改为疏水性。这样的疏水性基底可以利用范德华力吸附憎水性有机物,实现样品的前处理。表面增强拉曼光谱(SERS)在拉曼光谱的基础上发展而来,可以在在粗糙金属表面上检测被吸附的分子的拉曼特性,是目前最灵敏的检测手段之一。SERS常是以粗糙的Ag、Cu或Au金属表面作为增强基底,现今已发展了多种复合材料的新型基底体系。增强拉曼基底的结构和形貌直接影响着检测灵敏度,制备适合用于实际环境分析的SERS基底意义十分重大。便携式拉曼光谱仪可以与多种样品前处理手段联用,从而能够形成快速高效的检测体系,用于环境或医学等方面的监测。本文以过滤法负载在滤纸上的银纳米线膜作为SERS基底,主要进行了以下工作:(1)将银纳米线膜作为样品前处理-SERS联用基底,当磺胺分子接触到银纳米线膜时,磺胺分子的氨基和可以银形成相互作用力,使得它可以吸附在银纳米线膜上而完成待测分子的富集,用便携式拉曼仪直接得到SERS信号。我们用该基底检测了 4种常见的磺胺药品,通过定性和定量分析,证明其对于磺胺类药品有实际检测功能。同时,我们采用过滤法制作的银纳米线膜可以进行重复性利用,保证了基底的实用以及经济性。此种样品富集与SERS联用的分析手段减少了复杂的样品前处理步骤,大大缩短了分析时间,是一种原位快速检测磺胺类药物的方法。(2)我们提供了一种疏水性的丙硫醇修饰的银纳米线膜(PTH-Ag NMs)联立便携式拉曼光谱仪用于柔性原位擦拭萃取检测PAHs的方法。PTH通过银和硫之间的共价键修饰在银纳米线膜上,产生了疏水性膜结构。使用溶剂进行擦拭萃取的过程,与幼儿口鼻和玩具的接触过程相似,可以做到玩具中PAHs的溶出模拟。通过仪器的表征分析探究了基底疏水性与修饰硫醇的链长和修饰浓度的关系,并解释了硫醇在银纳米线膜上修饰的机理。玩具表面几种典型的多环芳烃例如荧蒽、蒽和芘,都可以用PTH-Ag NMs进行富集和灵敏地检测。
[Abstract]:It is very important to evaluate the effective components of environmental pollutants in daily life, which is closely related to environmental development and human health. The so-called active component, which can be dissolved or easily extracted, is considered to be the most relevant part of organism bioaccumulation, biosorption and bioconversion. The rapid field analysis of the active components of environmental pollutants can complete the preliminary screening of the illegal substances in a short time and realize the high efficiency monitoring process. The process of separation, purification and enrichment before detection has great influence on the subsequent detection, which makes it necessary to develop a simple and time-saving method for sample pretreatment. Precious metal substrates can form chemical bonds with functional groups such as sulfhydryl or amino groups and are directly adsorbed by the substrate to separate and enrich the samples containing sulfur / nitrogen. The surface of precious metals can also be self-assembled by chemical bonds to form modified layers, such as gold, silver and copper, which can bind to mercaptan molecules. Because the alkyl end of mercaptan aggregates to form a hydrophobic region, the respective surfaces are changed from the original hydrophilicity to hydrophobicity. This hydrophobic substrate can be used to adsorb hydrophobic organic compounds by van der Waals force to achieve sample pretreatment. Surface-enhanced Raman spectroscopy (SERS) has been developed on the basis of Raman spectroscopy. It can be used to detect the Raman properties of molecules adsorbed on rough metal surfaces, which is one of the most sensitive detection methods at present. SERS is usually determined by rough Ag,. The metal surface of Cu or Au has been used as a reinforced substrate, and a variety of new composite substrates have been developed. The structure and morphology of enhanced Raman substrate directly affect the detection sensitivity. It is very important to prepare a SERS substrate suitable for environmental analysis. The portable Raman spectrometer can be combined with a variety of sample pretreatment methods to form a rapid and efficient detection system for environmental or medical monitoring. In this paper, silver nanowire membrane loaded on filter paper was used as SERS substrate. (1) silver nanowire membrane was used as sample pretreatment and SERS substrate, when sulfonamide molecule came into contact with silver nanowire membrane, The sulfanilamide molecule can form an interaction force with silver, which can be adsorbed on the silver nanowire film to achieve the enrichment of the molecule to be tested. The SERS signal can be obtained directly by the portable Raman spectrometer. Four common sulfanilamide drugs were detected by using this substrate. It was proved by qualitative and quantitative analysis that it has practical function for the detection of sulfonamides. At the same time, the silver nanowire membrane prepared by filter method can be used repeatedly, which ensures the practicality and economy of the substrate. This method of sample enrichment combined with SERS reduces the complex sample pretreatment steps and greatly shortens the analysis time. It is a rapid in situ detection of sulfanilamides. (2) We provide a hydrophobic silver nanowire film (PTH-Ag NMs) modified with propanol for flexible in situ wipe extraction. (2) We provide a novel portable Raman spectrometer for the detection of hydrophobic propyl thiol modified silver nanowires (PTH-Ag NMs). PTH is modified on silver nanowires by covalent bonds between silver and sulfur. Hydrophobic membrane structure was produced. The process of wiping and extracting with solvent is similar to the contact process of toddler's mouth, nose and toy, which can simulate the dissolution of PAHs in toy. The relationship between the hydrophobicity of the substrate and the chain length and the modified concentration of modified mercaptan was investigated by means of the characterization analysis of the instrument, and the mechanism of the modification of mercaptan on silver nanowires was explained. Several typical PAHs on toy surfaces such as fluoranthene anthracene and pyrene can be enriched and detected sensitively by PTH-Ag NMs.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X830;O657.37

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