基于量子点的分析传感界面构建及其用于环境中污染物的分析检测

发布时间：2018-01-29 05:01

本文关键词： 量子点纳米粒子荧光检测分子印迹对硝基苯酚铜离子　出处：《山东师范大学》2017年硕士论文　论文类型：学位论文

【摘要】：近年来,环境中硝基酚类持久性污染物以及重金属污染等问题日益严重,对人们的健康造成严重威胁,因此相应的分析检测手段的发展显得尤为重要。半导体纳米晶体量子点,具有光稳定性好、尺寸可控、量子产率高、表面可进一步修饰等特点,在荧光传感分析领域中广泛应用。本文制备了两种基于量子点的新型荧光纳米粒子,应用于环境中污染物的识别和检测。主要内容如下:(1)基于量子点分子印迹的荧光纳米粒子用于检测环境水样中的对硝基苯酚利用简单的一锅法表面印迹技术,制备出荧光印迹纳米粒子。2-氨基乙基甲基丙烯酸酯盐酸盐首先吸附在羧基化的CdTe量子点表面,修饰后的量子点既可作为支持材料同时也是荧光信号源。通过自由基聚合过程直接在量子点表面形成超薄的印迹壳层,去除模板分子对硝基苯酚后,得到表面具有大量特异性识别位点的荧光印迹纳米粒子,能够实现对于目标物高灵敏度和选择性的特异性识别与检测,检测限为0.05μmol/L。应用于海水和湖水中对硝基苯酚的检测,回收率在93 109%之间,相对标准偏差在3.1 4.8%之内,该传感器在环境水样中对硝基苯酚的分析方面有良好的应用前景。(2)功能型ZnS:Mn~(2+)量子点纳米粒子的制备及其对Cu~(2+)离子的检测设计了一种新型的量子点纳米粒子用于Cu~(2+)离子的比率传感检测。首先利用简单的水热法合成掺杂Mn~(2+)的ZnS量子点,量子点光学性质稳定,具有双荧光发射峰。以L-半胱氨酸(L-cys)和6-巯基烟酸(MNA)对ZnS:Mn~(2+)量子点表面进行修饰后,由于二者能够与Cu~(2+)离子发生金属螯合作用,实现可视化比率检测铜离子。随着Cu~(2+)离子浓度的不断增加,纳米探针荧光颜色可以观察到由橙红到紫色的明显变化,在5-500 nmol/L的浓度范围呈良好的线性关系,最低检测限可达到1.2 nmol/L,并且对于其它共存离子具有较强的抗干扰能力,是一种能够快速、高效地实现铜离子检测的新型传感方法。
[Abstract]:In recent years, the problems of nitrophenol persistent pollutants and heavy metal pollution in the environment are becoming more and more serious, which pose a serious threat to people's health. Therefore, the development of corresponding analytical and detection methods is particularly important. Semiconductor nanocrystalline quantum dots have the characteristics of good optical stability, controllable size, high quantum yield and surface modification. It is widely used in the field of fluorescence sensing. In this paper, two novel fluorescent nanoparticles based on quantum dots have been prepared. For the identification and detection of pollutants in the environment. The main contents are as follows: 1). Fluorescent nanoparticles based on quantum dot molecular imprinting were used to detect p-nitrophenol in environmental water samples using a simple one-pot surface imprinting technique. Fluorescent imprinted nanoparticles. 2-aminoethyl methacrylate hydrochloride was firstly adsorbed on the surface of carboxylated CdTe quantum dots. The modified QDs can be used as both a supporting material and a fluorescent signal source. Through the free radical polymerization process, ultrathin imprinted shell layer was formed on the surface of the QDs, and the template molecule p-nitrophenol was removed. Fluorescent imprinted nanoparticles with a large number of specific recognition sites on the surface were obtained, which can be used to identify and detect the target materials with high sensitivity and selectivity. The detection limit was 0. 05 渭 mol / L. The method was applied to the determination of p-nitrophenol in seawater and lake water. The recovery was between 93 ~ 109% and the relative standard deviation was within 3. 1 ~ 4.8%. The sensor has a good application prospect in the analysis of p-nitrophenol in environmental water samples. (2) functional ZnS:Mn~(2) preparation of quantum dot nanoparticles and their effects on Cu~(2). A new type of quantum dot nanocrystalline was designed to detect the ratio of Cu~(2 ions. Firstly, ZnS quantum dots doped with Mn~(2 were synthesized by a simple hydrothermal method. The optical properties of QDs are stable and have double fluorescence emission peaks. The surface of QDs is modified by L-cys-L-cys) and 6-mercaptonicotinic acid (MNA). Because of the metal chelation between the two ions and the Cu~(2) ion, the visible ratio of copper ion can be detected. With the increasing of Cu~(2 ion concentration. The fluorescence color of the nanoprobe can be observed from orange red to purple, and there is a good linear relationship in the concentration range of 5-500 nmol/L. The minimum detection limit can reach 1.2 nmol / L and has strong anti-interference ability for other coexisting ions. It is a new sensing method which can detect copper ions quickly and efficiently.
【学位授予单位】：山东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X830;O657.3

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