氧化锌量子点的表面修饰及其在分子光谱分析中的应用

发布时间：2018-03-23 04:27

本文选题：传感器　切入点：水溶性　出处：《西南大学》2017年硕士论文　论文类型：学位论文

【摘要】：量子点作为一种新型的纳米发光材料,常常作为荧光标记物用于生物传感和细胞成像,而氧化锌量子点与传统量子点相比,不仅具有传统量子点的优良光学性质,还具有环境友好、无毒的性质,因此可以将其应用于环境、食品和医学等领域。对氧化锌量子点进行表面修饰,使氧化锌量子点在水溶液中保持稳定,能够极大地促进其在水样及生物样品中分析检测中的使用。本文通过对氧化锌量子点进行表面修饰,使其能够在水溶液中稳定保存,且保有良好的荧光特性,并将其应用于分析化学领域,构建新型传感器。主要研究内容如下:1.基于聚乙烯亚胺修饰的氧化锌量子点构建荧光方法间接测定白酒的酒精度在本研究中,通过两步法合成了能够很好的分散在乙醇溶液中的聚乙烯亚胺修饰的氧化锌量子点。并利用紫外吸收光谱、荧光光谱、红外光谱、高分辨透射电镜和场发射扫描电镜对聚乙烯亚胺修饰的氧化锌量子点进行了表征。聚乙烯亚胺修饰的氧化锌量子点在最佳激发(激发波长为355 nm)下发射黄绿色的荧光(最佳发射波长为527 nm)。在本研究工作中,利用聚乙烯亚胺修饰的氧化锌量子点在水中和乙醇中的荧光性质不同的原理,构建了测定酒精度的荧光方法。随着水分的增加,该量子点的荧光强度逐渐降低,该荧光方法在酒精度为20%-60%的范围内有一线性关系,能够检测实验室的人工样品,同时,利用该方法检测市场上的白酒,可以得到令人满意的结果。2.基于β-环糊精修饰的氧化锌量子点构建检测对硝基苯酚的荧光传感器在本研究工作中,通过一种简单的方法合成了一种水溶性较好的β-环糊精修饰的氧化锌量子点。合成的量子点的平均粒径约为3.64 nm,能够发射出黄色的荧光,并且利用高分辨透射电镜、紫外吸收光谱、荧光光谱和红外光谱对这一量子点进行了表征。该量子点可以被设计成检测对硝基苯酚的荧光传感器,该荧光传感器的检测范围在1.0-40μM之间,且其检测限为0.34μM。同时,将该传感器应用于实际水样的检测,得到很好的结果。同时,对其检测机理进行了研究,发现对硝基苯酚能够和β-环糊精进行络合作用,同时与氧化锌量子点之间进行电子转移,导致氧化锌量子点的荧光猝灭。3.基于β-环糊精修饰的氧化锌量子点构建检测钴离子的荧光探针在本研究工作中建立了一种基于β-环糊精修饰的氧化锌量子点检测钴离子的荧光方法,该荧光量子点有很强的黄绿色荧光并且能够很好的分散在水溶液中,此外对其用红外光谱、紫外光谱和高分辨透射电镜进行表征。研究发现,该量子点的荧光能够被钴离子猝灭,因此,发展了一种检测水溶液中钴离子的荧光探针。该荧光探针的检测范围是1.0-10μM,检测限是0.34μM,并且利用该探针分析水样中钴离子的情况,得到满意结果。最后对其猝灭机理进行了讨论,发现钴离子的加入会引起量子点的聚集,进而荧光猝灭,因此其机理有可能是聚集诱导猝灭。4.基于聚乙二醇修饰的氧化锌量子点构建检测铜离子的荧光传感器作为一种重要的重金属离子,铜离子会对其他的生物造成危害,因此需要建立一种高效、灵敏和有效的检测环境中铜离子数量的方法。在本研究工作中,首先合成了一种水溶性的聚乙二醇修饰的荧光氧化锌量子点,该量子点通过一种简单的合成方法将聚乙二醇修饰到氧化锌量子点表面,并利用荧光光谱、高分辨透射电镜、紫外吸收光谱和红外光谱对该量子点进行了表征。同时发现,该量子点的荧光能够被铜离子猝灭,因此,发展了一种检测水溶液中铜离子的荧光探针。该荧光探针有两个检测范围分别是1.0-10μM和10-200 nm,检测限是3.33 n M,并且利用该探针分析水样中的铜离子浓度,可以得到满意结果。最后对其猝灭机理进行了讨论,发现铜离子的加入会引起量子点的聚集,导致荧光猝灭,因此其机理可能是是聚集诱导猝灭。
[Abstract]:A new type of nano luminescent materials as quantum dots, are often used as a fluorescent marker for biosensing and cell imaging, and compared with the traditional Zinc Oxide quantum dot quantum dots, not only has excellent optical properties of traditional quantum dots, also has environmental friendly and non-toxic properties, so it can be applied in the environmental, food and medicine etc. Zinc Oxide field. Surface modification of quantum dots, Zinc Oxide quantum dots remained stable in aqueous solution, can greatly promote the analysis used in the detection of water and biological samples. Through surface modification of Zinc Oxide quantum dots, so that it can be kept stable in aqueous solution, and have good fluorescence characteristics, and its application in the field of analytical chemistry, construction of new sensors. The main contents are as follows: 1. Zinc Oxide quantum dots polyethyleneimine modified based on indirect fluorescence method Determination of liquor alcohol in this study, Zinc Oxide quantum dots polyethyleneimine modified can be well dispersed in the ethanol solution was synthesized by two steps. And using UV absorption spectroscopy, fluorescence spectroscopy, infrared spectroscopy, were characterized by high resolution transmission electron microscopy and field emission scanning electron microscopy of polyethyleneimine modified Zinc Oxide quantum dots. Polyethyleneimine modified Zinc Oxide quantum dots in optimum excitation (excitation wavelength is 355 nm) fluorescence emission yellow green (optimal emission wavelength of 527 nm). In this work, the principle of fluorescence properties of quantum dots using Zinc Oxide polyethyleneimine modified in water and ethanol in different construction. Fluorescence method for the determination of alcohol. With the increase of moisture content, the fluorescence intensity of the QDs decreased, the fluorescence method in the alcohol range of 20%-60% have a linear relationship, can. The laboratory test samples, at the same time, using the method of detection of liquor on the market, can get satisfactory results in.2. to construct the detection of p-nitrophenol fluorescence sensor in this work Zinc Oxide quantum dot cyclodextrin modified based on a Zinc Oxide quantum dot good water-soluble cyclodextrin modified was synthesized by a simple method. The average particle size of QDs is about 3.64 nm, which can emit yellow fluorescence, and high resolution transmission electron microscopy, UV absorption spectra, fluorescence spectra and IR spectra of the quantum dots were characterized. The quantum dots can be designed the fluorescence sensor of p-nitrophenol, the fluorescence sensor detection range between 1.0-40 M, and the detection limit was 0.34 M. at the same time, the detection of the sensor used in real samples, obtained very good results. At the same time, the The detection mechanism is studied, found that the complexation of p-nitrophenol and beta cyclodextrin, and between quantum dots and Zinc Oxide electron transfer, leading to fluorescence quenching of.3. quantum dots QDs Zinc Oxide Zinc Oxide beta cyclodextrin modified construction from the detection of cobalt fluorescence probe in this work established a fluorescence detection method of cobalt ion quantum dot Zinc Oxide beta cyclodextrin modified based on the fluorescent quantum dots have a strong yellow green fluorescence and can be well dispersed in aqueous solution, in addition to using infrared spectroscopy, UV spectroscopy and high resolution transmission electron microscopy characterization. The study found that the fluorescence quantum dots can be cobalt ion quenching, therefore, the development of fluorescent probe for detecting cobalt ions in aqueous solution. The detection range of the fluorescent probe is 1.0-10 M, the detection limit is 0.34 M, and the use of the probe The cobalt ion in water needle analysis, obtained satisfactory results. The quenching mechanism was discussed, found that the cobalt ion added will cause quantum dots aggregation, and fluorescence quenching, the mechanism may be aggregation induced quenching of.4. quantum dots Zinc Oxide PEGylated construct fluorescence sensor for the detection of copper ion as a based on the important heavy metal ions, copper ions will cause harm to other creatures, so it is necessary to establish an efficient, sensitive and effective method for quantitative detection of copper ions in the environment. In this work, we synthesized fluorescent quantum dots Zinc Oxide a water-soluble polyethylene glycol, the quantum point a a simple synthetic method of polyethylene glycol modified onto the surface of Zinc Oxide and the use of quantum dots, fluorescence spectroscopy, high resolution transmission electron microscopy, UV absorption spectra and infrared spectrum of the amount Quantum dots were characterized. At the same time, the fluorescence of the QDs can be copper ion quenching, therefore, the development of fluorescent probe for detection of copper ion in aqueous solution. The fluorescent probe with two detection range were 1.0-10 M and 10-200 nm, the detection limit is 3.33 n M, and the analysis of copper the ion concentration in water using the probe, can get satisfactory results. The quenching mechanism was discussed, found that the addition of copper ions can cause quantum dot aggregation induced fluorescence quenching, the mechanism may be induced by aggregation quenching.

【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.3;TB383.1

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