基于碳纳米材料的共振瑞利散射和荧光方法检测小分子的应用研究

发布时间：2018-07-21 19:20

【摘要】：近年来,碳纳米材料一直处于科学研究的前沿领域,各种各样的碳纳米材料层出不穷,从二维的石墨烯到一维的碳纳米管再到零维的富勒烯。其各自优越的物理化学性质,使其在光电领域、医学、生物工程、分析检测和催化等多个领域有着广泛的应用。本文建立了几种基于碳纳米材料的光谱平台,并将其应用于Al(Ⅲ)、过氧化氢和葡萄糖、自来水中活性氯的分析检测。本论文主要研究内容如下：1.基于铝离子增强的氯化血红素功能化氧化石墨烯(H-GO)共振瑞利散射信号,实现自来水、嘉陵江水样以及阿司匹林药片中痕量Al(Ⅲ)的检测。H-GO对Al(Ⅲ)有很灵敏的散射响应,随着Al(Ⅲ)浓度的增加,H-GO的散射信号增大,基于这种现象建立起检测Al(Ⅲ)的新方法。在最优条件下,测定Al (Ⅲ)的线性方程式AI/Io=0.5070+0.9872 C(R2=0.9975),相对应的线性范围是10nM-6μM检测限是0.87 nmol L-1。本实验应用了紫外-可见光谱、共振瑞利散射光谱、红外光谱对实验机理进行了研究,实验中发现EDTA的加入并不能猝灭增强的散射信号,说明在pH为5.9的条下,体系共振瑞利散射的增强应归因于生成的Al (OH)3胶体诱导了H-GO表面性质的改变。从紫外光谱图和红外光谱也可以推断出：Al(Ⅲ)加入后,氯化血红素(hemin)功能化石墨烯的电子转移到A1(OH)3胶体,H-GO表面亲水性的性质发生改变导致散射信号增强。2.基于石墨烯量子点-芬顿反应体系构建荧光检测过氧化氢和葡萄糖的新方法。芬顿试剂Fe2+和H202均不会猝灭石墨烯量子点(GQDs)的荧光,但是芬顿反应的产物Fe3+却能灵敏地猝灭GQDs的荧光,基于这种现象建立了间接检测过氧化氢的荧光新方法。同时,因为葡萄糖氧化酶能够特异性地氧化葡萄糖并伴随产生过氧化氢,因此该方法也适用于间接检测葡萄糖。本实验对体系的pH条件、反应温度、反应时间等实验参数进行了优化,在最优条件下,得到了检测过氧化氢的两段线性方程,分别是F-F0=42.8876 C-1.1229和F-F0=7.2123 C+219.5063,相对应的线性范围分别是0.5-6μmo\L-1和6-30μmolL-1;算出检出限(36/slope)是0.03 μmol L-1;在同样的最优条件下,检测葡萄糖也是呈现两段线性,分别是F-F0=26.5506 C+2.4915和F-F0=5.7736 C+172.4911,对应的线性范围是1-8μmolL-1和8-35μmolL-1,检出限为0.08μmol L-1。3.掺镁的碳量子点(Mg-CPNs)作为蓝色荧光传感器检测自来水中的活性氯。实验发现在pH为6.09的B-R缓冲溶液中Mg-CPNs在440nm处能发出稳定且温和的蓝色荧光,但是当加入一定量的活性氯时,Mg-CPNs的荧光会迅速猝灭,基于以上现象建立了一种快速、简易、灵敏、选择性检测水体中活性氯的荧光新方法。实验对体系的pH值、反应时间、Mg-CPNs的浓度进行了优化,在最优实验条件下得到检测活性氯的线性方程式为F-F0=723.369 C-23.01,对应的线性范围和检出限分别是50 nmol L-1-1.75μmol L-1和8 nmol L-1,最后我们将该方法应用于自来水中活性氯的检测,并得到了满意的结果。该实验能够用于检测活性氯可能是由于Mg-CPNs表面有很多含氧官能团提供的电子能够和强氧化性的活性氯发生作用,因而改变了Mg-CPNs表面的性质使得其荧光猝灭。
[Abstract]:In recent years, carbon nanomaterials have been in the forefront of scientific research, and a variety of carbon nanomaterials emerge in endlessly, from two-dimensional graphene to one-dimensional carbon nanotubes to zero dimension fullerenes. Their respective superior physical and chemical properties make them in the field of photoelectric, medicine, bioengineering, analytical detection and catalysis. Several spectral platforms based on carbon nanomaterials have been established and applied to the analysis and detection of active chlorine in Al (III), hydrogen peroxide and glucose, and water in tap water. The main contents of this paper are as follows: 1. based on the aluminum ion enhanced hemin functionalized graphene oxide (H-GO) resonance Rayleigh scattering signal, The current tap water, the Jialing River water sample and the trace Al (III) in the aspirin tablets are sensitive to the Al (III) scattering response. With the increase of Al (III) concentration, the H-GO scattering signal increases. Based on this phenomenon, a new method for detecting Al (III) is established. Under the optimal condition, the linear equation AI/Io=0.5070+0.9872 of Al (III) is determined. C (R2=0.9975), the corresponding linear range is that the detection limit of 10nM-6 mu M is 0.87 nmol L-1.. The UV visible spectrum, resonance Rayleigh scattering spectrum and infrared spectrum are used to study the experimental mechanism. It is found that the addition of EDTA can not quench the enhanced scattering signal, indicating that the system resonances Rayleigh scattering under the pH of 5.9. The enhancement should be attributed to the formation of the Al (OH) 3 colloid to induce the change of the surface properties of the H-GO. From the UV and IR spectra, it is also inferred that after the addition of Al (hemin), the electron transfer to the A1 (OH) 3 colloid of the fossils of the hemin (hemin) function to the A1 (OH) colloid, the change of the surface hydrophile property of the H-GO surface leads to the enhancement of the scatter signal based on the stone. A new method of fluorescence detection of hydrogen peroxide and glucose was constructed by the Fenton reaction system of the Fenton reaction. Both Fenton's reagent and H202 did not quenched the fluorescence of the graphene quantum dots (GQDs), but the product Fe3+ of the Fenton reaction could be sensitive to quenching the fluorescence of GQDs. Based on this phenomenon, a new method for the indirect fluorescence detection of hydrogen peroxide was established. At the same time, because glucose oxidase can oxidize glucose specifically and produce hydrogen peroxide, the method is also suitable for indirect detection of glucose. The experimental parameters such as pH condition, reaction temperature, reaction time and other experimental parameters are optimized. Under the optimal conditions, the two segment linear equation for detection of hydrogen peroxide is obtained. It is not F-F0=42.8876 C-1.1229 and F-F0=7.2123 C+219.5063, the corresponding linear range is 0.5-6 moL-1 and 6-30 mu molL-1, and the detection limit (36/slope) is 0.03 mol L-1. Under the same optimal conditions, the detection of glucose is also two segment linear, which is the corresponding linear norm. The carbon quantum dots (Mg-CPNs) with a detection limit of 0.08 Mu mol L-1.3. doped with magnesium (Mg-CPNs) were measured as a blue fluorescent sensor for the detection of active chlorine in tap water. It was found that Mg-CPNs at 440nm could produce a stable and mild blue fluorescein at 440nm at pH 6.09, but when a certain amount of active chlorine was added, Mg-CPNs was added to the B-R buffer solution, but when a certain amount of active chlorine was added, Mg-CPNs was found, Mg-CPNs. A fast, simple, sensitive and selective fluorescence method for the detection of active chlorine in water is established based on the above phenomenon. The pH value, reaction time and Mg-CPNs concentration of the system are optimized. The linear equation of the detection of active chlorine is F-F0=723.369 C-23.01 and the corresponding line is obtained under the optimal experimental conditions. The range and detection limit are 50 nmol L-1-1.75 mol L-1 and 8 nmol L-1 respectively. Finally, we apply this method to the detection of active chlorine in tap water and obtain satisfactory results. The experiment can be used to detect active chlorine on the surface of the Mg-CPNs, which has many oxygen functional groups provided by oxygen and strong oxidizing active chlorine. Thus, the fluorescence of Mg-CPNs is quenched by changing the properties of the surface.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ127.11;O657.3

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