基于表面增强拉曼光谱法的新型化学传感器研究

发布时间：2018-01-09 02:19

本文关键词：基于表面增强拉曼光谱法的新型化学传感器研究　出处：《吉林大学》2017年博士论文　论文类型：学位论文

【摘要】：近年来,表面增强拉曼光谱法(SERS)已成为最具潜力的一种分析方法。由于它具有灵敏度高、光谱信息丰富、易操作、检测速度快等优势,特别适合应用于食品和环境分析。到目前为止,如何提高检测方法的灵敏度和选择性、拓展可检测的物质种类,成为SERS传感器进行定量分析的最大瓶颈,它吸引了大量科研工作者的兴趣。基于SERS原理,利用便携式的激光拉曼光谱仪器,我们成功的研究了几种测定食品和水中有机小分子和无机离子的SERS传感器。具体研究工作主要分为以下几个部分:1.测定乳制品中三聚氰胺的SERS传感器。我们在传统银镜反应的基础上,通过添加α-环糊精,阻碍银镜的形成,绿色地合成了一种环糊精修饰的银纳米粒子(CD-Ag NPs)。使用CD-Ag NPs作为SERS基底,构建了一种测定乳制品中三聚氰胺的SERS传感器。相比传统银基底,该基底对于三聚氰胺更敏感,增强因子可达106。系统考察了CD-Ag NPs溶液、Na Cl溶液、Na OH溶液和三聚氰胺溶液的用量,以及反应的混合时间等条件对三聚氰胺检测结果的影响。结果表明,SERS传感器测定三聚氰胺的线性范围为5.0~100μg L~(-1),线性相关系数为0.9995,检出限为3.0μg L~(-1),通过分析牛奶和奶粉样品,其回收率在89~104%,相对标准偏差小于10%。2.测定环境水中Hg~(2+)的超灵敏SERS传感器。我们研究了一种利用甲巯咪唑功能化的CD-Ag NPs作为基底。高灵敏度和选择性检测环境水中Hg~(2+)的SERS传感器。在p H=10的含有Na Cl的溶液中,502 cm~(-1)处出现了甲巯咪唑的特征拉曼峰。当加入Hg~(2+)后,拉曼信号显著减弱,这种减弱与Hg~(2+)的浓度在一定范围内成比例。使用响应曲面分析法对SERS传感器实验条件进行了系统优化。SERS传感器测定Hg~(2+)的线性范围为50~150μg L~(-1),检出限为0.10μg L~(-1)。常见的金属离子对测定Hg~(2+)的实验结果影响不大,方法选择性较好。该方法应用于分析实际环境水样品,其加标回收率为98.5~105.2%,相对标准偏差小于3.5%。3.选择性测定环境水中邻苯二胺的SERS传感器。我们研究出一种选择性检测水中邻苯二胺(OPD)的SERS传感器。基于在酸性条件下OPD与亚硝酸根发生环化反应,生成苯并三氮唑(BTAH),间接的实现了对OPD的选择性检测。对反应介质的酸度、亚硝酸盐的浓度、反应时间以及与SERS基底和被分析物的混合时间进行了系统的优化。传感器测定OPD的线性范围为0.10~1.0μmol L~(-1),检出限为30 nmol L~(-1),定量限为100 nmol L~(-1)。通过相关结构类似物干扰实验发现该传感器对OPD具有较高的选择性。实际水样品加标实验,回收率在97.8~104.5%,相对标准偏差小于4%。4.基于衍生化反应的超灵敏甲醛SERS传感器。我们研究出一种选择性和超灵敏的检测食物和环境水中的痕量甲醛(HCHO)的SERS传感器。根据HCHO与4-氨基-5-肼基-3-巯基~(-1),2,4-三唑(AHMT)发生衍生化反应,生成产物6-巯基-5-三唑并[4,3-b]-s-三嗪(MTT)在832 cm~(-1)处拉曼光谱的变化,进行定量分析。对于衍生化反应的孵化时间,反应溶液的体积和混合时间进行了优化。传感器测定HOMO的线性范围为1~1000μg L~(-1),检出限为0.15μg L~(-1),定量限为0.45μg L~(-1)。通过测定2种环境水样和2种食物加标样品,得到回收率范围为64.0~111.1%,该方法的测定结果与国家标准方法相比,无显著性差异。5.基于罗丹明键合氨基化SiO_2包覆Au-Ag核壳纳米棒测定环境水中Hg~(2+)的SERS传感器。我们设计了一种基于水解反应的新型Hg~(2+)SERS传感器。使用罗丹明6G(R6G)衍生物通过形成Schiff碱的方式化学键合到氨基功能化的SiO_2包覆Au-Ag核壳纳米棒作为SERS基底,该基底表现出了卓越的增强因子和稳定性。基于化学键在纳米结构表明的良好可调控能力,显著的提高了SERS传感器的选择性和敏感性,对Hg~(2+)的检出限为0.33 pmol L~(-1)。此外,基底还表现出了对p H的良好响应能力。该传感器通过结合便携式激光拉曼光谱仪有望实现对Hg~(2+)和p H进行现场快速测定。6.基于罗丹明衍生物的一种新型荧光和SERS双信号p H传感器。我们设计合成了一种新型的罗丹明衍生物RGP,用作p H传感探针。该探针的传感原理是基于RGP在不同p H值下,分子螺内酰胺结构发生开-关环变化,表现出不同的荧光和SERS信号改变。RGP的酸度值(p Ka)和荧光量子产率值分别为2.43(±0.14)和0.48。当p H在1.0~4.0时,RGP的荧光变化是可逆的。p H在3.29和6.09之间更换5次之后SERS信号的变化很小。常见的无机离子和有机物对于传感系统几乎没有影响。该传感系统有望应用于测定酸性生物样品的p H值。
[Abstract]:In recent years, surface enhanced Raman spectroscopy (SERS) analysis has become one of the most promising method. Because it has abundant spectral information, high sensitivity, easy operation, fast detection speed and other advantages, especially suitable for food and environmental analysis. So far, how to improve the detection sensitivity and selectivity, expand can detect the material types, become the biggest bottleneck for the quantitative analysis of the SERS sensor, it attracted a lot of researchers interest. Based on the principle of SERS, using laser Raman spectroscopy instrument portable, we successfully developed SERS sensor for determination of food and water of small organic molecules and inorganic ions. Some specific research work is mainly divided into the following part 1.: Determination of several SERS sensors of melamine in dairy products. We are based on the traditional silver mirror reaction, by adding alpha cyclodextrin, hinder the formation of silver mirror, green Color synthesis of a cyclodextrin modified silver nanoparticles (CD-Ag NPs). Using CD-Ag NPs as a SERS substrate, constructed a determination of melamine in dairy products SERS sensor. Compared with the traditional silver substrate, the substrate is more sensitive to melamine, the enhancement factor of up to 106. lines through CD-Ag NPs test solution and Na Cl solution Na, OH solution and melamine solution dosage, reaction condition and influence of mixing time on the melamine test results. The results show that the SERS sensor for determination of melamine concentration range of 5.0~100 g L~ (-1), the linear correlation coefficient was 0.9995, the detection limit was 3 G L~ (-1), through the analysis of milk and the milk powder samples, the recovery rate was 89~104%, the relative standard deviation is less than 10%.2. in environmental water by Hg~ (2+) of the ultra sensitive SERS sensor. We study a use of methimazole functionalized CD-Ag NPs as substrate. The sensitivity and selectivity of detection of environmental water Hg~ (2+) SERS sensor. In the solution containing Na Cl P H=10, 502 cm~ (-1) appeared the characteristic Raman peak. When adding Hg~ methimazole (2+), Raman signal is reduced, and the reduced Hg~ (2+) ratio in a certain range the use of concentration. The response surface analysis on the experimental conditions of SERS sensor system optimization.SERS sensor for determination of Hg~ (2+) of the linear range of 50~150 g L~ (-1), the detection limit was 0.10 g L~ (-1). The common metal ions on the determination of Hg~ (2+) had little effect on the experimental results. The method has good selectivity. The method was applied to the analysis of the actual environmental water samples, the recovery rate was 98.5~105.2%, the relative standard deviation is less than 3.5%.3. SERS sensor selective determination of phthalate two amines. We developed a selective determination of phthalate two amine (OPD) SERS. . under acidic conditions OPD and nitrite cyclization reaction based on the synthesis of benzo triazole three (BTAH), indirect realized selective detection of OPD. The reaction medium acidity, nitrite concentration, reaction time and mixed with SERS substrate and the analyte at the system optimization. Sensor for determination of the linear range of the OPD 0.10~1.0 mol L~ (-1), the detection limit was 30 nmol L~ (-1), the limit of quantification was 100 nmol L~ (-1). Through analogue interference experiments showed that this sensor has high selectivity for OPD. The actual water sample experiments, recovery rate in 97.8~104.5%, the relative standard deviation is less than 4%.4. of the derivatization reaction of formaldehyde sensor based on ultra sensitive SERS. We developed a trace formaldehyde selectivity and ultrasensitive detection of food and water (HCHO) SERS sensor. According to the HCHO and 4- amino hydrazine -5- -3- 6 Based on ~ (-1), 2,4- three (AHMT) of derivatization reaction, product 6- -5- three mercapto triazole and [4,3-b]-s- were three (MTT) in 832 cm~ (-1) change of Raman spectra, were quantitatively analyzed. The derivatization reaction incubation time, reaction solution volume and mixing time were optimization of sensor. The linear range were HOMO 1~1000 g L~ (-1), the detection limit was 0.15 g L~ (-1), the quantitative limit was 0.45 g L~ (-1). Through the determination of 2 water samples and 2 kinds of food samples with standard, recovery rate in the range of 64.0~111.1%, the method of determination of the results compared with the national standard method, no significant difference in.5. based on the Luo Danming bond of amino SiO_2 coated Au-Ag nanorods in environmental water by Hg~ (2+) SERS sensor. We designed a new type of hydrolysis of Hg~ (2+) based on SERS sensor. Using the Luo Danming 6G (R6G) through the formation of Schiff base derivatives the party Type of chemical bonding to the amino functionalized SiO_2 coated Au-Ag nanorods as SERS substrate, the substrate showed remarkable enhancement factor and stability. The chemical bonds in the nano structure shows good control ability based on improve the selectivity and sensitivity of the SERS sensor, the Hg~ (2+) detection limit 0.33 pmol L~ (-1). In addition, the base also showed a good response ability of P H to Hg~. The sensor is expected to achieve by combining the portable laser Raman spectrometer (2+) and P H.6. field rapid determination of a novel fluorescent SERS derivative and Luo Danming double signal sensor based on H P we design. Synthesis of novel derivatives of RGP p H Luo Danming, is used as a sensing probe. The sensing principle of the probe is RGP P at different H values based on the molecular structure of spirolactams on-off ring changes showed different fluorescence and SER The S signal change of.RGP (P Ka) and the pH value of the fluorescence quantum yield values were 2.43 (+ 0.14) and 0.48. P H as in 1.0~4.0, the fluorescence change of RGP is reversible after.P H replaced 5 times in 3.29 and 6.09 between the variation of the SERS signal is very small. The common inorganic ions and organic compounds almost no impact on the sensor system. The sensing system is expected to be applied to the determination of acid biological samples P H value.

【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O657.37;TP212.2

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