面向多环芳烃快速分析的固相萃取和表面增强拉曼光谱联用技术

By the reason of the increasingly severe environmental hazards of polycyclic aromatic hydrocarbons (PAHs), the development of a rapid analysis technique for is PAHs is in urgent.Due to the complexity of the environmental sample matrix, we have to realize a combination of the proper sample pre-preparation method and analysis approach, which can not only maintain the high sensitivity of the analysis results and confidence, but also greatly reduce the analysis time and analysis errors. In this issue, we chose solid phase extraction (SPE) and surface-enhanced Raman spectroscopy (SERS) (as the sample pre-preparation method and the analysis approach, respectively) to prepare a filter with excellent extraction capacity and outstanding Raman enhancement performance via function-oriented synthesis and specific modification. The filler was assembled as an entire column with sample pre-preparation and analysis functions and the extraction behavior and Raman detective features of PAHs on this column were studied systematically. We used standard Raman spectroscopy database and appropriate spectral analysis to realize the qualitative analysis of PAHs. The corresponding relationship of the extracts and the stationary phase in a complete extraction mode of SPE was used to realize the quantitative detection of PAHs by choosing the Raman spectrum of the stationary phase as an internal standard. Finally, a combination of SPE and SERS techniques for the rapid analysis of PAHs is established.

面对日益严峻的多环芳烃类物质的环境危害，急切需要发展一种针对多环芳烃的快速分析技术。环境样品基质的复杂性，迫使我们必须选用合适的样品前处理和分析测定方法联用，才可以既保持分析结果的高灵敏度和置信度，还可以极大地减少分析时间和分析误差。在本课题中，我们选用固相萃取的表面增强拉曼光谱技术分别作为样品前处理和分析测定方法，通过功能导向合成和特异性修饰制备既保持优异萃取能力，又具有卓越的拉曼增强能力的填料。将填料组装成前处理测定一体柱，并系统的研究多环芳烃在柱上的萃取行为和拉曼检测特征。利用标准拉曼光谱数据库和适当的光谱解析实现多环芳烃的定性分析，借助固相萃取的完全萃取模式和被萃取物与固定相的空间对应关系，并采用固定相的拉曼光谱作为内标，进而实现多环芳烃的定量检测。最终，建立一种面向多环芳烃快速分析的固相萃取-表面增强拉曼光谱（SPE-SERS）联用方法。

在本课题中，我们选用固相萃取和表面增强拉曼光谱技术分别作为样品前处理和分析测定方法，通过固相萃取-表面增强拉曼一体化实现了对痕量多环芳烃的高灵敏检测。我们所做的工作主要包括：一、合成了一系列具有表面增强拉曼活性的基底：电化学方法制备多孔银丝；在银箔上定向化学沉积二维ZnO制备超疏水拉曼基底；利用溶剂热合成制备无序的银纳米线膜；恒电位沉积制备超疏水金纳米颗粒；晶种法制备可自清洁的ZnO-Au基底。二、对基底进行特异性修饰：探究了不同链长硫醇修饰对多环芳烃萃取效果的差别并选定丙硫醇为修饰剂通过疏水作用实现多环芳烃类待测物的萃取；探究基底表面修饰剂静电相互作用力对待测物的富集能力；利用超声剥离法制备了二维g-C3N4纳米片考察了其吸附机理。三、对固相萃取与SERS进行一体化组装并对性能进行评价与优化应用于多环芳烃痕量测定：通过表面增强拉曼基底表面的功能化利用亲疏水作用力富集多环芳烃并实现了nM级的超灵敏检测；将该一体化方法用于实际水样与儿童玩具表面的多环芳烃类物质痕量测定；优化固相萃取-表面增强拉曼一体柱实现固相萃取的微型化。通过本项目一系列的工作，最终，建立一种面向多环芳烃快速分析的固相萃取-表面增强拉曼光谱（SPE-SERS）联用方法。