【作者】 刘钊；

【导师】 宁桂玲； 叶俊伟；

【作者基本信息】 大连理工大学 ， 化学工艺， 2010， 硕士

【摘要】 作为典型的重金属离子,人们很早就对汞离子的毒性有所认识,寻找能快速准确检测汞离子的方法具有重要意义。分子荧光传感能将分子间的相互作用转变成为荧光信号传递给外界,因为它兼具便捷、专一和灵敏的优点,并能对化学体系和生命体系中的分析对象进行适时原位检测,近年来备受关注,成为超分子化学领域中最重要的研究课题之一。一般的荧光探针(包括荧光淬灭型和荧光增强型)的荧光强度容易受外界因素的影响,基于电荷转移(CT)机理的新型探针能够较好的消除这些因素的干扰,提供更加准确的测量数据。本论文以酰胺基团为识别基团,合成了一系列酰胺化合物作为汞离子荧光探针,检测了它们对金属离子的识别特性。主要研究内容包括：1.合成了6种具有潜在识别能力的双臂及三臂酰胺化合物(化合物1—6),经过核磁和质谱表征,确定了它们的结构。并且利用水热结晶法组装了超分子有机晶体(化合物7),研究了氢键对超分子结构的稳定和分子荧光效率的影响。2.讨论了浓度、pH值对酰胺化合物1—6的荧光光谱的影响,确定了测量荧光的最佳浓度和稳定pH区间。在此基础上,研究了化合物1—6对常见阴离子和金属离子的识别效果,研究表明,汞离子对化合物2有很强的荧光淬灭作用,向化合物5、6中加入汞离子引起荧光发射峰位红移。3.对化合物5、6的汞离子识别性能进行了详细研究。研究表明,化合物5、6对汞离子具有专一识别性,通过酰胺脱氢与汞离子配位,根据分子内电荷转移(ICT)原理,加入汞离子后分子荧光峰位红移,在紫外灯照射下肉眼可以观察到荧光颜色的变化,通过荧光强度的变化和Job法共同确定了化合物5、6与汞离子的配位比为1：1,并且其他金属离子的存在对汞离子识别不构成干扰。更多还原

【Abstract】 As a typical heavy metal, Mercury has been known as a toxic metal since antiquity. To monitor and prevent mercury pollution, efforts are being made worldwide to develop new mercury detecting strategies for monitoring mercuric ion from the environment and biological samples, now several techniques are available. Fluorescent molecular sensing has attracted much attention over the years for its many inherent merits including high specificity and high sensitivity. As a link of material science and analysis chemistry, the study in fluorescent sensor and novel sensor material has received a growing attention with the rapid development of cross subject. This technology has been widely used for the real-time in situ detection of the molecular events both in the environmental chemical, analytic chemistry, and bio-medicinal science. The fluorescence intensities of common probes (both fluorescence quenching and fluorescence enhancement) are influenced by experimental factors such as photobleaching, excitation intensity, the micro-environment around the dye, and the concentration of the dye. The new probes based on the mechanism of charge transfer (CT) can normalize the variation of these effects and provide more robust and precise measurement results. In this work, the design, synthesis, and photophysical properties of six amide receptor fluorescent molecular sensors are presented. Moreover, sensing properties are also investigated. The results are shown as follows:1. A series of novel fluorescent probes for metal ions with amide receptor are designed and synthesized. A supramolecular complex has been synthesized under hydrothermal condition. This complex shows photoluminescence property indicating that it may be applied in the development of luminescent materials.2. The influence of concentration and pH value is investigated. On this basis, we find a new probe (compound 2) based on the mechanism of photoinduced electron transfer (PET) can be used to indicate Hg (Ⅱ) for its "ON-OFF" property. We also get another two new probes for their red-shift in fluorescence-emission after adding the Hg (Ⅱ).3. The amide receptor derived from 1,4-benzenedicarbonyl chloride and N-phenyl-o-phenylenediamine (compound 5) and another amide receptor derived from benzene-1,3,5-tricarbonyl chloride and N-phenyl-o-phenylenediamine (compound 6) could be used to specifically bind Hg2+ ion in acetonitrile solution by an amide deprotonation mechanism. We find these new fluorescent probes sense Hg (II) by means of a spctrofluorometer with a large red-shift in emission (blue to green). Investigated results revealed that only Hg (II) can significantly be discerned.更多还原