有机改性气凝胶涂层用于管内固相微萃取的研究

发布时间：2019-05-27 05:36

【摘要】：样品基质复杂、待测组分的含量较低等因素促使样品前处理成为样品分析的关键环节。有效的样品前处理技术可以降低杂质的干扰,浓缩痕量组分,提高分析方法的灵敏度。固相微萃取是一种集采样、萃取、浓缩、进样于一体的样品前处理技术,具有操作简便,精确度高,易于与分析仪器联用实现在线分析等优点。常规固相微萃取适用于与气相色谱联用检测沸点低、热稳定性高的分析物,但对于大多数沸点高,热不稳定性分析物难以实现有效富集分析。管内固相微萃取可以方便与高效液相色谱联用,实现对大部分目标分析物有效的萃取与分析。纤维填充型管内固相微萃取是一种独特的管内固相微萃取形式,它不仅增大了涂层面积,而且降低管内死体积,有效改善峰形,增加萃取效率并提高分析准确度。但目前涂层种类有限、选择性差、使用寿命短是制约纤维管内固相微萃取的主要因素。气凝胶是一种性质十分优异的纳米三维立体网络多孔材料,其巨大的比表面积及丰富的种类使其在在管内固相微萃取方面具有良好的应用潜力。本论文将气凝胶材料进行有机功能化改性,在玄武岩纤维和钛丝表面制备有机改性气凝胶涂层,将其置于PEEK管内制备出管内固相微萃取装置,与液相色谱在线联用实现在线富集分析环境中常见的多环芳烃和环境雌激素等重要污染物。主要研究内容及结果如下:1.以绿色环保的玄武岩纤维为基体,在其表面制备间苯二酚改性的三聚氰胺气凝胶作为萃取涂层,置于PEEK管内制备出管内固相微萃取装置,并对涂层进行了扫描电镜及红外光谱表征。选择多类物质考察了涂层的萃取选择性,选择萃取效率最高的8种多环芳烃作为模型分析物,分别对萃取流速、体积、有机溶剂含量、离子强度、pH值和脱附时间进行了优化。在最佳条件下,得出各物质的检测限在0.01-0.05μg L-1之间,线性范围为0.03-100μg L-1,日内与日间重现性相对标准偏差在1.9-3.9%和3.9-7.4%之间,并成功应用于实际水样中多环芳烃的分析检测。2.在玄武岩纤维表面制备对苯二甲醛改性的二氧化硅气凝胶萃取涂层,装填萃取管,对涂层及纤维基体进行了扫描电镜及红外光谱表征。与液相色谱在线联用考察了萃取选择性,以5种环境雌激素为模型分析物,对萃取流速、体积、有机溶剂含量、离子强度、pH值和脱附时间等影响萃取效率的因素进行了优化。在最优条件下,各物质的检测限在0.01-0.05μg L-1之间,线性范围为0.06-100μg L-1,富集倍数在2364-3132之间。该方法被成功应用于对实际样品中雌激素的分析。3.利用聚氨酯改性的二氧化硅气凝胶涂层对玄武岩纤维进行功能化,装填PEEK管制得固相微萃取装置。以环境雌激素作为模型分析物,分别考察了萃取流速、样品体积、有机溶剂含量、离子强度、pH值和脱附时间对萃取及洗脱效率的影响。在最佳条件下,各物质工作曲线的线性系数在0.9991-0.9998之间,线性范围为在0.10-50μg L-1和0.03-100μg L-1之间,检测限在0.01-0.03μg L-1之间,所建立的分析方法应用到实际样品的检测。4.以钛丝为基体,制备聚多巴胺改性的氧化石墨烯气凝胶作为萃取涂层装填PEEK管得到固相微萃取管,考察了萃取与洗脱条件。在最佳条件下,得出各物质的线性范围为0.03-50μg L-1,检出限最低达到0.01μg L-1,萃取重现性的相对标准偏差在0.77-3.65%之间,萃取管的制备重现性相对标准偏差低于5%,成功应用于对食品盒,煤灰样品的检测,表明该萃取材料在管内固相微萃取方面具有良好的应用价值。
[Abstract]:The sample matrix is complex, the content of the component to be tested is lower, and the pretreatment of the sample is the key link of the sample analysis. The effective sample pretreatment technology can reduce the interference of impurities, concentrate trace components, and improve the sensitivity of the analytical method. Solid-phase microextraction is a kind of pre-sample processing technique for sampling, extraction, concentration and injection. It has the advantages of simple and convenient operation, high precision, and easy to be combined with analytical instrument to realize on-line analysis. The conventional solid-phase microextraction is suitable for the analysis of low boiling point and high thermal stability in combination with gas chromatography, but for most of the high boiling point, the thermal instability analysis is difficult to realize the effective enrichment analysis. The solid-phase micro-extraction in the tube can be conveniently combined with high performance liquid chromatography to achieve the effective extraction and analysis of most of the target analytes. The solid-phase microextraction in a fiber-filled tube is a unique form of solid-phase micro-extraction in a tube, which not only increases the area of the coating, but also reduces the dead volume in the tube, effectively improves the peak shape, increases the extraction efficiency and improves the analysis accuracy. However, the coating types are limited, the selectivity is poor, and the short service life is the main factor to restrict the solid-phase micro-extraction in the fiber tube. Aerogel is a kind of three-dimensional, three-dimensional, three-dimensional network porous material with very excellent properties, and its large specific surface area and rich species make it have good application potential in solid-phase micro-extraction in the tube. The method comprises the following steps of: carrying out organic functional modification on the aerogel material, preparing an organic modified aerogel coating on the surface of the basalt fiber and the titanium wire, and placing the organic modified aerogel coating in the PEEK tube to prepare the solid-phase micro-extraction device in the tube; And can realize on-line enrichment and analysis of important pollutants such as polycyclic aromatic hydrocarbons and environmental estrogens in an on-line enrichment analysis environment by using the liquid chromatography on-line. The main contents and results are as follows:1. Based on the green and environment-friendly basalt fiber, a resorcinol-modified melamine aerogel is prepared as an extraction coating on the surface of the base, and a solid-phase micro-extraction device in the tube is prepared in the PEEK tube, and the coating is characterized by scanning electron microscopy and infrared spectroscopy. The extraction rate, volume, organic solvent content, ionic strength, pH value and desorption time were optimized. Under the best condition, the detection limit of each substance is between 0.01 and 0.05. mu. g L-1, the linear range is 0.03-100 & mu; g L-1, the relative standard deviation of the intra-day and the day reproducibility is 1.9-3.9% and 3.9-7.4%, and the detection of the polycyclic aromatic hydrocarbon in the real water sample is successfully applied. A modified silica aerogel extraction coating was prepared on the surface of the basalt fiber, the extraction tube was filled, and the coating and the fiber matrix were characterized by scanning electron microscope and infrared spectroscopy. The factors such as extraction flow rate, volume, organic solvent content, ionic strength, pH value and desorption time were optimized by on-line combination with liquid chromatography. Under the optimal conditions, the detection limit of each substance is between 0.01 and 0.05. mu; g L-1, the linear range is 0.06-100 & mu; g L-1, and the enrichment factor is between 2364 and 3132. The method was successfully applied to the analysis of the estrogen in the actual sample. The basalt fiber is functionalized with a polyurethane modified silica aerogel coating, and the solid phase micro-extraction device is filled with PEEK. The effects of extraction flow rate, sample volume, organic solvent content, ionic strength, pH value and desorption time on the extraction and elution efficiency were investigated. Under the best conditions, the linear coefficient of the working curve of each substance is between 0.9991 and 0.9998, the linear range is between 0.10-50 & mu; g L-1 and 0.03-100 & mu; g L-1, the detection limit is between 0.01-0.03 & mu; g L-1, and the established analytical method is applied to the detection of the actual sample. A solid-phase micro-extraction tube was prepared by using the titanium wire as a matrix to prepare the polydopamine-modified graphene oxide aerogel as an extraction coating, and the extraction and elution conditions were investigated. Under the best condition, the linear range of each substance is 0.03-50 & mu; g L-1, the detection limit is at least 0.01 & mu; g L-1, the relative standard deviation of the extraction reproducibility is between 0.77 and 3.65%, the relative standard deviation of the extraction tube is less than 5%, and the extraction tube is successfully applied to the food box, The detection of the coal ash sample shows that the extraction material has good application value in the solid-phase micro-extraction of the tube.
【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O658.2

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