基于CdTe、ZnS：Mn量子点的荧光免疫分析

发布时间：2018-02-03 00:31

本文关键词： 荧光免疫分析荧光共振能量转移 ZnS Mn量子点 CdTe量子点金黄色葡萄球菌肠毒素B 快速检测　出处：《湖南师范大学》2012年硕士论文　论文类型：学位论文

【摘要】：金黄色葡萄球菌肠毒素B(SEB)是由一种革兰氏阳性球菌产生的常见的食物毒素。作为一种超抗原,SEB在炎症过程中起到非常重要的作用。它也是过敏性疾病中的一种重要的致敏原。由于其内在的高稳定性、强毒性和易散播的特性,SEB还是一种潜在的生物武器。所以发展一种快速、简便、灵敏的SEB检测新方法具有非常重要的意义。荧光免疫分析灵敏度高、特异性好,是一种应用十分广泛的生物、生化分析技术。鉴此,本论文在本实验室前期研究的基础上,首先建立了一种以CdTe量子点作为能量供体、荧光染料Alexa Fluor568(AF568)作为能量受体的荧光共振能量转移分析体系,用来快速检测SEB毒素。但是考虑到Cd系列量子点的毒性,本论文进一步建立了基于ZnS掺Mn低毒性量子点的荧光免疫分析,并将之用于毒素SEB的快速、灵敏检测,以应对食品安全监测的迫切需要。本论文工作主要内容： 1.综述了荧光免疫分析技术的应用以及现阶段常用于荧光分析中的不同荧光标记物；论述了新兴的荧光标记物低毒性ZnS:Mn量子点的制备方法和应用现状；简述了SEB的危害以及现有的检测方法。 2.制备了水溶性CdTe量子点及其磁性荧光纳米复合物；对相关性能进行了表征；利用磁性荧光复合物和荧光染料建立了快速检测SEB毒素的FRET分析体系。 3.采用水相共沉淀法制备了Mn掺杂的ZnS量子点；X射线衍射和透射电镜测试结果表明该量子点具有闪锌矿型结构,为直径19nm的球型颗粒；荧光测试表明所制备的量子点具有窄而对称的发射峰,发光波长在580nm左右,为耀眼的橙色光。 4.结合磁性纳米粒子的免疫磁分离和ZnS:Mn量子点的免疫荧光标记,采用“夹心式三明治”免疫分析法对SEB毒素进行了检测,最低检测限为0.01ng/mL,具有较好的灵敏度。 5.建立了一种以硝酸纤维素膜为抗体固定载体的荧光免疫分析方法；该方法简便快速,具有一定的灵敏度(检测限为0.1ng/mL)。
[Abstract]:Staphylococcus aureus enterotoxin BPSEB is a common food toxin produced by Gram-positive cocci. It is a superantigen. SEB plays a very important role in the process of inflammation. It is also an important allergen in allergic diseases, due to its inherent high stability, strong toxicity and easy to spread characteristics. SEB is also a potential biological weapon, so it is very important to develop a rapid, simple and sensitive SEB detection method. Fluorescent immunoassay has high sensitivity and specificity. It is a widely used biological and biochemical analysis technology. Therefore, this paper is based on the previous research in our laboratory. Firstly, a fluorescence resonance energy transfer analysis system using CdTe quantum dots as energy donor and fluorescent dye Alexa Fluor568 as energy receptor was established. But considering the toxicity of CD series quantum dots, the fluorescence immunoassay based on ZnS doped mn low toxicity quantum dots was further established. It is applied to the rapid and sensitive detection of toxin SEB in order to meet the urgent need of food safety monitoring. 1. The application of fluorescent immunoassay (FIA) and the different fluorescent markers commonly used in fluorescence analysis at present are reviewed. The preparation methods and application status of new fluorescent labeled low toxicity ZnS:Mn quantum dots are reviewed in this paper. The harm of SEB and the existing detection methods are briefly described. 2. The water-soluble CdTe quantum dots and their magnetic fluorescent nanocomposites were prepared. The related properties were characterized. A FRET analysis system for rapid detection of SEB toxin was established by using magnetic fluorescent complex and fluorescent dye. 3. Mn-doped ZnS quantum dots were prepared by water-phase coprecipitation. The results of X-ray diffraction and transmission electron microscopy show that the quantum dots have sphalerite structure and are spherical particles with a diameter of 19 nm. Fluorescence measurements show that the quantum dots have a narrow and symmetrical emission peak and the luminescence wavelength is about 580 nm. 4. Combined with the immunomagnetic separation of magnetic nanoparticles and the immunofluorescence labeling of ZnS:Mn quantum dots, the SEB toxin was detected by sandwich immunoassay. The lowest detection limit is 0.01 ng / mL, which has good sensitivity. 5. A fluoroimmunoassay method based on nitrocellulose membrane was established, which is simple, rapid and sensitive (detection limit is 0.1ng / mL ~ (-1)).
【学位授予单位】：湖南师范大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：O657.3;R114

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