基于碳点的荧光探针的制备与发光性能的研究

发布时间：2018-05-15 21:31

  本文选题：碳点 + 荧光探针　； 参考：《天津工业大学》2017年硕士论文

【摘要】：荧光碳点是一类粒径小于10 nm的新型纳米材料。由于具有小尺寸、卓越的水溶性、好的生物相容性、低细胞毒性、高的光稳定性、可调的激发和发射行为及表面易于功能化,使其广泛应用在众多领域,如分析检测、生物成像、光催化等。本文分别采用水热法、煅烧法及回流法合成了一系列碳点,主要研究了其发光性能,并将其应用于生物成像、分析检测和光催化剂的设计。论文的主要内容包括以下几部分:1.本实验首先用水热法制备了荧光碳点:以已二酸和柠檬酸铵制备的CD1能够作为Hg2+的荧光探针,通过实验发现CD1在4-18 μ的线性范围内可以实现定量检测,在细胞中通过观察荧光的变化可以识别对其Hg2+进行分析;以卡波姆934与二乙烯三胺为原料制得CD2,Co2+与碳点通过金属配键作用使其溶液发生肉眼可见的颜色变化并且荧光猝灭,在0-40 μ线性范围内可以定量检测,并且可以应用于实际水样中Co2+的分析检测;通过无水柠檬酸和4,7,10-三氧-1,13-十三烷二胺制备的CD3与多巴胺通过静电作用螯合荧光猝灭,而随着Al3+或者谷胱甘肽(GSH)的加入,可以从螯合物中夺取多巴胺释放碳点使其荧光恢复,另外该探针还可以在生物体液中检测多巴胺,在食物样品中检测Al3+和人体血清中检测到GSH。2.然后用煅烧法合成了疏水性碳点CD4,通过实验证明得到的碳点能够在有机溶剂中很好的溶解,并且在乙醇中能够选择性地快捷灵敏的检测Hg2+;进一步通过CTAB修饰制得两亲性CD5,构建了基于荧光共振能量转移(FRET)机理的荧光检测体系,实现表明CD5能够作为有效的能量供体,将其能量转移给受体桑色素-Al3+,实现对Al3+的定性及定量分析,另外该体系由于细胞无毒性可应用于细胞中Al3+的识别与成像。3.设计了一步回流法制备CD6,实验发现该碳点不仅具有下转换荧光性质,而且还具有优秀的上转换荧光性质,建立了一种操作简单的多功能荧光检测体系。当以下转换为激发源时,CD6能够高选择性地检测三硝基苯酚(TNP),在0-50 μM线性范围内定量检测;当以上转换为激发源时,TNP不能使其荧光发生猝灭,而Fe3+使其荧光增强,在8-40 μM浓度范围内,荧光变化与Fe3+呈现很好的线性关系可以实现定量检测。4.合成了基于碳点的光催化剂,碳点优异的荧光性质能够拓宽催化剂可利用光的范围,提高催化效率。通过在WO3表面修饰碳点,得到的CDs/WO3在可见光照射下具有很强的光的吸收。相比于纯WO3和CDs,该复合物具有较高的光催化活性,经0.5小时光照后,亚甲基蓝的降解率可达到100%;另外用CD6修饰氮化碳(C3N4),得到的复合物CD6/C3N4在可见光照射下其催化效果高于纯C3N4和CD6。最后解释了这两种光催化剂具有高效催化活性的机理。
[Abstract]:Fluorescent carbon dots are a new kind of nanomaterials with particle size less than 10 nm. Due to its small size, excellent water solubility, good biocompatibility, low cytotoxicity, high photostability, adjustable excitation and emission behavior and easy surface functionalization, it is widely used in many fields, such as analytical detection, Biological imaging, photocatalysis, etc. In this paper, a series of carbon spots were synthesized by hydrothermal method, calcination method and reflux method, respectively. The luminescent properties of carbon spots were studied and applied to biometric imaging, analysis and detection, and the design of photocatalyst. The main contents of the thesis include the following parts: 1. In this experiment, the fluorescent carbon points were prepared by hydrothermal method. CD1 prepared by adipic acid and ammonium citrate could be used as a fluorescence probe for Hg2. It was found that CD1 could be quantitatively detected in a linear range of 4-18 渭. The Hg2 can be identified and analyzed by observing the changes of fluorescence in the cells, and the color change of the solution can be seen by metal bond and quenching of fluorescence, which is made from Carbomer 934 and diethylenetriamine. It can be quantitatively detected in the range of 0-40 渭, and can be applied to the analysis and detection of Co2 in real water samples. CD3 prepared from anhydrous citric acid and 4o 710- trioxy-1-tridecanediamine and dopamine can be chelated to fluorescence quenching by electrostatic interaction. With the addition of Al3 or glutathione (GSH), dopamine releasing carbon can be captured from the chelate to recover its fluorescence. In addition, the probe can detect dopamine in biological fluid, Al3 in food samples and GSH.2in human serum. Then the hydrophobic carbon spot CD4 was synthesized by calcination method. The experimental results show that the carbon spots can be dissolved in organic solvents and can be used to detect Hg2 quickly and selectively in ethanol. Furthermore, the amphiphilic CD5 was prepared by CTAB modification, and a fluorescence detection system based on fluorescence resonance energy transfer (fret) mechanism was constructed. The results show that CD5 can act as an effective energy donor and transfer its energy to the receptor Morin Al3. The qualitative and quantitative analysis of Al3 can be realized. In addition, the system can be applied to the recognition and imaging of Al3 in cells because of its nontoxicity. A one-step reflux method was designed to prepare CD6. It was found that the carbon point had not only downconversion fluorescence properties but also excellent up-conversion fluorescence properties. A multifunctional fluorescence detection system with simple operation was established. When the following conversion is an excitation source, TNP6 can be detected with high selectivity and quantificationally in the linear range of 0-50 渭 M. when the above conversion is an excitation source, it can not quench its fluorescence, while Fe3 enhances its fluorescence. In the range of 8-40 渭 M, the linear relationship between fluorescence change and Fe3 can be achieved. The photocatalyst based on carbon point was synthesized. The excellent fluorescence property of carbon point can widen the range of light available and improve the catalytic efficiency. By modifying the carbon point on the surface of WO3, the CDs/WO3 has strong light absorption under visible light irradiation. Compared with pure WO3 and CDS, the complex has higher photocatalytic activity, and the degradation rate of methylene blue can reach 100 after 0.5 hours of illumination, and the CD6/C3N4 modified with CD6 is more effective than that of pure C3N4 and CD6 under visible light irradiation. Finally, the mechanism of high activity of these two photocatalysts was explained.
【学位授予单位】：天津工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.3

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中国期刊全文数据库 前1条

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本文编号：1894041