荧光碳点的制备与性质研究

发布时间：2018-05-03 15:08

本文选题：碳点 + 荧光　；参考：《华东师范大学》2017年博士论文

【摘要】：荧光碳点由于其良好的生物兼容性和制备方法的简便性受到了广泛的关注。本论文主要采用电化学法和水热法制备了一系列荧光碳点。研究了碳点作为能量给体用于DNA杂化的检测、反应物对碳点性能的影响、聚集效应对碳点荧光性质的影响。具体如下:1.采用碳棒作为工作电极和对电极,银/氯化银作为参比电极,通过电化学氧化的方法,制备了绿色荧光的碳点,并对其形貌和荧光性能进行了表征。将所制备的荧光碳点作为能量给体,能过带正电的聚合物聚二甲基二烯丙基氯化铵(PDADMAC)作为电荷桥梁,与Cy3荧光染料标记的单链DNA通过电荷间的作用形成"三明治"结构,构建了基于荧光共振能量转移(FRET)的DNA杂化检测平台,实现了对目标DNA的定量检测。2.以磷酰基乙酸三乙酯为原料,在磷酸的存在下通过水热法,制备了磷掺杂的、水溶性的荧光碳点。研究了磷掺杂碳点的荧光性质,发现了随着荧光碳点的浓度增大,碳点的荧光发射峰红移;降低浓度导致荧光发射峰蓝移。通过实现证实了所发现的荧光红移现象是由于碳点的聚集所导致。3.研究了反应物对所得到的氮掺杂荧光碳点性能的影响。采用柠檬酸或者葡萄糖作为碳源,4,7,10-三氧-1,13-十三烷二胺或者多巴胺作为氮源,两两组合,通过水热法制备了四种碳点。通过透射电子显微镜(TEM)和原子力显微镜(AFM)对所制备的碳纳米点进行形貌表征之后,通过对它们光学性质,电化学性质的研究,发现反应原料不仅仅影响其荧光性能,也影响了其它的理化性能,如pH敏感性、光伏性能。其中用4,7,10-三氧-1,13-十三烷二胺作为氮源制备的碳点,比多巴胺作为氮源所制备的碳点具有更高的荧光量子产率;而用多巴胺作为氮源制备得到的碳点,因为其表面含有多巴胺或者多巴胺类似物的结构,具有更高的pH敏感性。此外,用多巴胺作为氮源的所制备的两种碳点不仅具有荧光特性,同时还表现出电化学活性,为通过原料的选择制备多功能荧光碳点提供了一个新的思路。4.采用具有电化学活性的溴化乙锭(EB)作为反应物,通过水热法制备了荧光碳点,其荧光峰位于510 nm,并且不随激发波长的变化而变化。循环伏安法测试结果表明,在pH为0.54时,所得到的碳点于-0.63出现了一还原峰,并且随着pH的增大,还原峰正移。该特性可用于pH变化检测。
[Abstract]:Fluorescent carbon points have been widely concerned because of their good biocompatibility and the simplicity of preparation methods. In this paper, a series of fluorescent carbon dots were prepared by electrochemical method and hydrothermal method. The effects of carbon dots as energy donors on the detection of DNA hybrid, the effect of the reactants on the carbon point energy and the carbon point fluorescence properties of the carbon dots were studied. The effects are as follows: 1. using carbon rods as working electrodes and opposite electrodes, silver / silver chloride as a reference electrode, the carbon points of green fluorescence are prepared by electrochemical oxidation, and their morphology and fluorescence properties are characterized. The prepared fluorescent carbon points can be used as an energy donor and can lead to a positive polymer of poly (two methyl diene). Propyl ammonium chloride (PDADMAC) is used as a charge bridge and the single strand DNA marked by Cy3 fluorescent dye forms a "sandwich" structure. A DNA hybrid detection platform based on fluorescence resonance energy transfer (FRET) is constructed. The quantitative detection of the target DNA is achieved by using three ethyl phosphoacetoacetate as the raw material and the presence of phosphoric acid in the presence of phosphoric acid. The fluorescence properties of phosphorus doped carbon dots were studied by over hydrothermal method. The fluorescence properties of phosphorus doped carbon point were studied. It was found that the fluorescence emission peak of the carbon point was red shift with the increase of the concentration of the fluorescent carbon point, and the decrease of the concentration resulted in the blue shift of the fluorescence emission peak. The results showed that the fluorescence redshift found by the fluorescence was caused by the aggregation of carbon points. 3. the effects of the reactant on the properties of nitrogen doped fluorescent carbon were investigated. Four kinds of carbon points were prepared by using citric acid or glucose as carbon source, 4,7,10- three oxygen -1,13- thirteen alkane two amine or dopamine as nitrogen source, and 22 combinations by hydrothermal method. The preparation was prepared by transmission electron microscopy (TEM) and atomic force microscopy (AFM). After characterization of the carbon nanodots, through the study of their optical properties and electrochemical properties, it is found that the reaction material not only affects its fluorescence properties, but also affects other physical and chemical properties, such as pH sensitivity and photovoltaic performance. The carbon points prepared by 4,7,10- three oxygen -1,13- thirteen alkanes as nitrogen source are compared with dopamine as nitrogen source. The carbon dots prepared have higher fluorescence quantum yields, and the carbon points produced by dopamine as a nitrogen source, because the surface contains dopamine or dopamine analogues, with higher pH sensitivity. In addition, the two kinds of carbon dots prepared with dopamine as nitrogen sources have not only fluorescence characteristics but also electrochemistry. The study activity provides a new idea for the preparation of multi-functional fluorescent carbon points through the selection of raw materials..4. uses electrochemically active ethidium bromide (EB) as a reactant, and the fluorescent carbon point is prepared by hydrothermal method. Its fluorescence peak is located at 510 nm and does not change with the change of the excitation wavelength. Cyclic voltammetry test results show that in pH At 0.54, a reduction peak appeared in -0.63, and the reduction peak shifted positively with the increase of pH. This characteristic can be used for pH change detection.

【学位授予单位】：华东师范大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O657.3

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