【作者】 秦品珠；

【导师】 牛承岗； 曾光明；

【作者基本信息】 湖南大学 ， 环境科学与工程， 2010， 博士

【摘要】 环境污染问题越来越严重,环境中污染物的种类正在被不断的发现,污染物的数量也在不断增加,对环境中污染物分析手段的灵敏度,准确性,特异性及方便性等方面的要求也越来越高。环境中污染物的分析手段有很多种,其中荧光分析法由于其具有灵敏度高、选择性较好等的优点越来越受到了国内外研究者的关注。本论文主要是进行了一系列发光性能优良的可以发长寿命荧光的稀土配合物、普通荧光的萘酰亚胺、葸衍生物及等荧光染料的设计与合成,并进行了在环境中病原微生物、金属离子、微量水等方面的监测应用。所发展的方法都具有高灵敏度,操作方便等优点。主要完成内容如下：(1)提出了一种基于两探针串联的环境中常见病原微生物DNA的监测方法。该模型包括了捕获探针DNA1,识别探针DNA2和目标探针DNA3。合成了几种具有长寿命荧光的稀土三元配合物,并选择发光性能最好的：以噻吩甲酰三氟丙酮(TTA),5-氨基邻菲啰啉(5-NH2-phen)为配体的稀土铕配合物,Eu(TTA)3(5-NH2-phen), (ETN),然后通过修饰连接上免疫球蛋白：ETN-IgG,利用反相微乳液法,制备表面修饰活性基团的核壳型纳米颗粒。这样的纳米颗粒能够十分便利地连接上寡聚核苷酸链以用于时间分辨荧光检测。同时,根据已报道的金黄色葡萄球菌和大肠杆菌特异性基因片段用软件Primer Premier 5.0设计了实验所需的捕获探针,识别探针和目标探针序列。杂交过程中,先将带氨基的捕获探针DNA1共价固定在普通载玻片上,然后与识别探针DNA2,目标探针DNA3在玻片表面进行杂交。最后,通过检测玻片表面的荧光强度来达到监测病原微生物的目的。这种方法具有选择性好、杂交稳定性好、高灵敏度和杂交时间短等优点,是一种微生物病原体监测的有效方法(第2章)。(2)在基于发光纳米颗粒的两探针串联的监测模型上,建立了一种直接用长寿命发光单分子为标记物的病原微生物的监测方法。用既带有活性基团又能发长寿命荧光的稀土铕配合物,Eu(TTA)3(5-NH2-phen)直接作为标记物。这种检测方法操作起来更加方便。并且具有杂交时间短,稳定性令人满意,选择性好等优点。(第3章)。(3)合成了一种新型的硫脲类荧光探针,9-蒽醛缩氨基硫脲(AnthT),并研究了该探针在测定环境样品中痕量Hg(Ⅱ)和Cu(Ⅱ)的应用。通过研究不同金属离子,Na(Ⅰ), Al(Ⅲ), Ba(Ⅱ), Mn(Ⅱ), Co(Ⅱ), Cd(Ⅱ), Ca(Ⅱ), Zn(Ⅱ), Cr(Ⅲ), Fe(Ⅲ), Pb(Ⅱ), Hg(Ⅱ)及Cu(Ⅱ)(相同浓度：5.0×10-5 mol L-1)对AnthT荧光强度的作用,发现只有Hg(Ⅱ)和Cu(Ⅱ)对AnthT的有显著的荧光猝灭作用。在pH为7.2,激发波长为411 nm的情况下,AnthT在水-乙醇溶液(20/5 v/v)中的荧光强度随着Cu(Ⅱ)或Hg(Ⅱ)浓度的增加慢慢降低。此外,在一定的金属离子浓度范围内该硫脲类染料的荧光强度和金属离子的浓度呈良好的线性关系,对Hg(Ⅱ)和Cu(Ⅱ)监测的线性范围分别为2×10-6-4×10-5 mol L-1和1×10-7-1×10-5 mol L-1。该传感系统表现出了令人满意的灵敏度,操作方法简便,并且对于Hg(Ⅱ)和Cu(Ⅱ)的检测限低至8.9×10-8 mol L-1和3.3×10-8 mol 1-1。该探针可以用于实际样品中Hg(Ⅱ)和Cu(Ⅱ)浓度的测定(第4章)。(4)合成了一种新型的对极性敏感,具有可共聚端基双键、性能优良的荧光载体,N-烯丙基-4-吗啉基-1,8-萘酰亚胺(AMN)。将AMN通过末端双键在紫外光照下共价固定到硅烷化的玻片表面。然后对其进行实验研究,实验结果表明,在激发波长400 nm处,随着水含量的增加,AMN的荧光强度显著降低。在有机溶剂中水含量为0.00%至4.40%之间的时候,AMN的荧光强度和水含量呈现了很好的线性关系。该传感体系表现出了令人满意的重现性,具有灵敏度高,响应速度快等优点。同时,通过共价固定的方法也大大减少了荧光载体的流失,提高了传感器的稳定性。另外,所制备的传感体系对环境体系的pH不敏感,并且具有至少一个月的长使用寿命(第5章)。(5)合成了又一种对极性敏感的苯并噻吨二羧酸酐衍生物,N-(2-甲基丙烯酰胺)-苯并[k,1]噻吨-3,4-二甲酰亚胺(MBTD),该发光分子也通过末端双键共价固定到玻片表面,用于监测有机溶剂中的水含量。实验考察了不同有机溶剂对荧光载体的影响。结果表明溶剂极性对荧光载体的强度和斯托克斯位移都有着显著的作用。在一定的水含量浓度范围内,荧光强度与浓度呈现了良好的线性关系。该传感器具有响应速度快,重现性好等优点,足以应用于实际样品中微量水含量的测定(第6章)。(6)在制备各种荧光传感体系的过程中,也合成了一系列新型的荧光物质。在最后一章中,主要介绍了其他一些发光性能良好的荧光物质的合成(第7章)。更多还原

【Abstract】 With the increasing of the variety and the amounts of environmental pollutants, the demands for the sensitivity, accuracy, specificity, and accessibility et al. of analytical methods of environmental pollutants become higher and higher. There are many methods to analyze pollutants however, more and more researchers at home and abroad pay attention to fluorescence analytical methods for its high sensitivity, selectivity and other advantages. In this dissertation, a series of novel fluorescence dyes of rare earth complexes with long life fluorescence time, naphthalimide, and anthracene derivatives were designed and synthesized. The dyes were then applied in the detection of pathogenic microorganisms, trace metal ions, or water content in envrionment. The developed detection systems both have satisfactory sensitivity and were easy to operation.The details are summarized as follows:(1) A two-probe tandem DNA hybridization assay including capture DNA1, probe DNA2, and target DNA3 was prepared. Some kinds of rare earth complex were synthesized. The long-lived luminescent europium complex doped nanoparticles (NPs) were used as the biomarker. The complex included in the particle was Eu(TTA)3(5-NH2-phen)-IgG (ETN-IgG), the europium complex Eu(TTA)3(5-NH2-phen) linking an IgG molecule. Silica NPs containing ETN-IgG were prepared by the reverse microemulsion method, and were easy to label oligonucleotide for time-resolved fluorescence assays. The luminophores were well-protected from the environmental interference when they were doped inside the silica network. The sequences of Staphylococcus aureus and Escherichia coli genes were designed using software Primer Premier 5.0. Amino-modified capture DNA1 was covalently immobilized on the common glass slides surface. The detection was done by monitoring the fluorescence intensity from the glass surface after the hybridization reaction with the NPs labeled probe DNA2 and complementary target DNA3. The sensing system presented short hybridization time, satisfactory stability, sensitivity, and selectivity. This approach was successfully employed for preliminary application in the detection of pure cultured E. coli, it might be an effective tool for pathogen DNA monitoring (chapter 2).(2) Based on the above detection assay, the single molecule with a functional group of amino and strong long lifetime fluorescence was directly used as the biomarker. The Eu complex of Eu(TTA)3(5-NH2-phen) was linked to the probe DNA. High sensitivity showed that the proposed DNA detection system based on such complex molecular could be more convenient than nanoparticle-based detection systems. The sensing system presented short hybridization time, satisfactory stability, and high selectivity (chapter 3).(3) A novel fluorescent dye,9-anthraldehyde-thiosemicarbazone (AnthT), used for the determination of Cu(Ⅱ) or Hg(Ⅱ) in aqueous solutions was described. In the presence of several metal ions such as Na(Ⅰ), Al(Ⅲ), Ba(Ⅱ), Mn(Ⅱ), Co(Ⅱ), Cd(Ⅱ), Ca(Ⅱ), Zn(Ⅱ), Cr(Ⅲ), Fe(Ⅲ), Pb(Ⅱ), Hg(Ⅱ), and Cu(Ⅱ) at a same concentration of 5.0×10-5 mol L-1, only Hg(Ⅱ) and Cu(Ⅱ) resulted in remarkable decreases. The fluorescence intensity of the probe decreased with increasing concentration of Cu(Ⅱ) or Hg(Ⅱ) when it was excited at 411nm in water-ethanol (20/5 v/v) solutions at pH 7.20. The fluorescence intensity of the probe decreased with increasing concentration of Cu(Ⅱ) or Hg(Ⅱ). The thiourea derivative-based probe showed linear response toward Hg(Ⅱ) in the concentration range ca.2×10-6-4×10-5 mol L-1 and Cu(Ⅱ) ca. 1×10-7-1×10-5 mol L-1. The prepared sensing system presented satisfactory sensitivity and selectivity, and the detection limits could be as low as 8.9x10"8 mol L-1 for Hg(Ⅱ) and 3.3×10-8 mol L-1 for Cu(Ⅱ). The developed method was successfully employed for preliminary application in natural water and domestic sewage (chapter 4).(4) A new fluorescent dye, N-allyl-4-morpholinyl-1,8-naphthalimide (AMN), was synthesized as a fluorescent indicator in the fabrication of a sensor for determining water content in organic solvents. AMN was photo-copolymerized on a glass surface treated with a silanizing agent. The fluorescence intensity of AMN decreased with increasing water contents when it was excited at 400 nm. In the range of ca.0.00-4.40%(v/v), the fluorescence intensity of AMN changed as a linear function of water content. The sensor exhibited satisfactory reproducibility, reversibility, and a quick response time. The leakage of the fluorophore was successfully prevented through covalently immobilization. Additionally, the prepared sensor is pH-insensitive and possesses a relatively long lifetime of at least one month (chapter 5).(5) Another benzothioxanthene derivative of N-(2-methacryloxyethyl) benzo[k,l]thioxanthene-3,4-dicarboximide (MBTD), was used as a fluorescent indicator for determination of water content in organic solvents. MBTD was also photocopolymerization-immobilized on a glass surface. Fluorescence spectra of the sensing membrane were recorded in various solvents of different polarity. The solvent exerted an evident influence on the fluorescence intensities and stokes shift. And the fluorescence intensity of MBTD changed as a linear function of water content in a certain range. The prepared sensor system possesses short response, and recovering time. The reversibility and reproducibility are also adequate for practical measurement (chapter 6).(6) While preparing various fluorescence sensing systems, other novel fluorescence dyes were synthesized. In the last chapter, synthesis of some other fluorescence dyes with super luminescence properties were described (chapter 7).更多还原