【作者】 麻秋娟；

【导师】 俞汝勤； 沈国励；

【作者基本信息】 湖南大学 ， 分析化学， 2009， 博士

【摘要】 基于有机载体的光化学传感研究是传感器研究中极为活跃的领域,寻找具有高选择性的新型有机分子识别载体用于化学传感研究是一项十分有意义的工作。针对探针和传感器在灵敏度和选择性等方面存在的问题,结合我们实验小组相关研究工作成果,论文完成的主要工作是:依据荧光探针的一般设计原理和信息传递机制,设计合成了一系列新型荧光探针用于重金属离子的检测;由于共价固定法在荧光传感器构建过程中具有染料不易流失、使用寿命长、机械性能好等优点,设计合成了一些新型的可供共价固定的荧光载体,并应用于重金属离子的荧光化学传感器研究。具体内容如下:1.在第2章中,构建了一种基于N-甲基四苯基卟啉（NMTPPH）荧光增强型探针用于Zn2+的检测。当Zn2+存在时,N-甲基-5, 10, 15, 20-四苯基卟啉（NMTPPH）的荧光发射强度增强。研究结果表明:该探针和Zn2+形成了1:1的络合物,以此为基础进行Zn2+的定量检测;该探针对Zn2+的线性响应范围为5.0×10-7 -1.0×10-5 mol/L,检测下限为1.5×10-7 mol/L。除Cu2+外,大部分的碱金属、碱土金属和过渡金属离子对Zn2+的测定无明显干扰。将该探针用于水样中Zn2+的测定,其测量结果良好。2.在第3章中,研制了一种基于酰胺喹啉衍生物的比率型荧光探针用于Zn2+的检测。该荧光探针可在pH为7.24的乙醇/水（v:v=1:1）溶液中对Zn2+进行高选择性识别。当有Zn2+存在时,探针的荧光发射强度增强,同时最大荧光发射波长红移。对此探针的分析性能进行了系统研究,研究结果表明:探针与Zn2+形成了1:1的络合物,对Zn2+的线性响应范围是2.0×10-6-5.0×10-5 mol/L,检测下限是2.7×10-7 mol/L。将该探针用于自来水和湘江水中Zn2+的测定,所得结果较好。3.在第4章中,发展了一种基于苯并噁唑类化合物的比率型荧光传感器用于Zn2+的传感。为了构建此传感器,先合成末端带有双键的苯并噁唑类衍生物,再将其与甲基丙烯酸-β-羟乙酯（HEMA）通过紫外光（UV）照射在活化的玻片表面进行聚合。在没有Zn2+的pH为7.24溶液中,该荧光传感器通过激发态分子内质子迁移（ESIPT）在450 nm处有最大荧光发射峰;当有Zn2+存在时,由于ESIPT过程被抑制,最大荧光发射波长蓝移。因此,基于ESIPT原理可以构建一个比率型的荧光传感器以实现对Zn2+的灵敏检测。此传感器对Zn2+表现出良好的选择性、较好的重现性以及快的响应速度。该传感器对Zn2+的线性响应范围是8.0×10-5 -4.0×10-3 mol/L,检测下限为4.0×10-5 mol/L。该传感器的光极膜具有很好的稳定性,有至少三个月的使用寿命。利用该传感器对自来水与湘江水中的Zn2+进行测定,均得到令人满意的结果。4.在第5章中,构建了一种基于萘酰亚胺类化合物的荧光传感器用于Cu²⁺的检测。为了构建此传感器,先合成末端带有双键的萘酰亚胺类衍生物作为荧光载体。为了阻止染料的流失,在紫外光（UV）照射下将该载体共价固定到硅烷化试剂活化的玻片表面进行构建传感界面。当Cu²⁺存在时该传感器的荧光被猝灭从而实现Cu²⁺的选择性识别。此激发波长在可见区的传感器对Cu²⁺表现出良好的选择性、较好的重现性以及快的响应速度。该传感器的光极膜具有很好的稳定性,有至少两个月的使用寿命。该传感器对Cu²⁺的线性响应范围是4.0×10-7 - 6.0×10-4 mol/L,检测下限为2.0×10-7 mol/L。利用该传感器对湘江水中的Cu²⁺进行检测,测定结果令人满意。5.在第6章中,制备了一种基于罗丹明-噻吩类化合物的荧光探针用于Hg²⁺检测。该探针可在pH为6.00的乙腈/水（v:v=1:1）溶液中对Hg²⁺进行检测,具有灵敏度高和选择性好等优点。当Hg²⁺存在时,该探针的荧光发射强度增强同时溶液的颜色也从无色变为粉红色,这些变化产生的可能原因是Hg²⁺络合导致探针的罗内酰胺结构开环。我们还系统考查了该荧光探针对Hg²⁺的分析性能。研究结果表明:探针和Hg²⁺形成了2:1的络合物,以此为基础实现对Hg²⁺的定量检测;该探针对Hg²⁺的线性响应范围是5.0×10-8-1.0×10-5 mol/L,检测下限是2.0×10-8 mol/L。将该探针用于自来水和湘江水中Hg²⁺的检测,测定结果令人满意。6.在第7章中,设计合成了一种基于罗丹明-香豆素类化合物的荧光探针用于Hg²⁺检测。该探针可在pH为7.24的乙醇/水（v:v=1:1）溶液中对Hg²⁺进行检测,具有灵敏度高和选择性好等优点。当Hg²⁺存在时,该探针的荧光发射强度增强同时溶液的颜色也从黄色变为粉红色,这些变化产生的可能原因是Hg²⁺络合导致探针的罗内酰胺结构开环。我们考查了该荧光探针对Hg²⁺的分析性能。研究结果表明:探针和Hg²⁺形成了1:1的络合物,以此为基础实现对Hg²⁺的定量检测;该探针对Hg²⁺的线性响应范围是8.0×10-8-2.0×10-5 mol/L,检测下限是4.0×10-8 mol/L。将该探针用于自来水和湘江水中Hg²⁺的检测,测定结果令人满意。更多还原

【Abstract】 In recent years, the research on chemical probes and sensors based on organic dyes remains very active and searching for new fluorophores to improve sensitivity and selectivity of chemical probes and sensors is still a challenge for the analytical research efforts. In this dissertation, a series of novel fluorescent probes and sensors were designed and synthesized to recognize heavy metal ions. The details are summarized as follows:1. In chapter 2, N-methyl-5, 10, 15, 20-tetraphenylporphine（NMTPPH） as an organic carrier has been used to detect trace amount of zinc ions in ethanol-water solution by fluorescence spectroscopy. The fluorescent probe undergoes a fluorescent emission intensity enhancement upon binding to zinc ions in EtOH/H2O （1:1, v/v） solution. The fluorescence enhancement of NMTPPH is attributed to the 1:1 complex formation between NMTPPH and Zn²⁺ which has been utilized as the basis for the selective detection of Zn²⁺. The linear response range covers a concentration range of Zn²⁺ from 5.0×10-7 to 1.0×10-5 mol/L and the detection limit is 1.5×10-7 mol/L. The fluorescent probe exhibits high selectivity over other common metal ions except Cu²⁺. And the probe has been used for determination of Zn²⁺ in water samples with satisfactory results.2. In chapter 3, a ratiometric fluorescent zinc probe of carboxamidoquinoline with a carboxylic acid group was designed and synthesized. Probe exhibits high selectivity for sensing Zn²⁺; increase in fluorescence emission intensity and red-shift of fluorescence emission are observed upon binding Zn²⁺ in EtOH/H2O （1:1, v/v） solution at pH 7.24. The ratiometric fluorescence response is attributed to the 1:1 complex formation between probe and Zn²⁺ which has been utilized as the basis for the selective detection of Zn²⁺. The analytical performance characteristics of the proposed Zn²⁺-sensitive probe were investigated. The probe can be applied to the quantification of Zn²⁺ with a linear range covering from 2.0×10?6 to 5.0×10?5 mol/L and a detection limit of 2.7×10?7 mol/L. The determination of Zn²⁺ in both tap and river water samples shows satisfactory results.3. In chapter 4, we describe the fabrication and analytical characteristics of fluorescence-based zinc ion-sensing glass slides. To construct the sensor, a benzoxazole derivative with a terminal double bond was synthesized and copolymerized with 2-hydroxyethyl methacrylate （HEMA） on the activated surface of glass slides by UV irradiation. In the absence of Zn²⁺ at pH 7.24, the resulting optical sensor emitted fluorescence at 450 nm via excited-state intramolecular proton transfer （ESIPT）. Upon binding with Zn²⁺, the ESIPT process was inhibited resulting in blue-shift of fluorescence emission. Thus, the proposed sensor can behave as a ratiometric fluorescent sensor for the selective detection of Zn²⁺. In addition, the sensor shows nice selectivity, good reproducibility and fast response time. The sensing membrane demonstrates a good stability with a lifetime of at least 3 months. The sensor exhibits a linear response toward Zn²⁺ in the concentration range 8.0×10-5-4.0×10-3 mol/L and the detection limit is 4.0×10-5 mol/L. The proposed chemosensor has been successfully implemented for the identification of Zn²⁺ in both tap and river water samples.4. In chapter 5, we describe the fabrication and analytical characteristics of fluorescence-based copper ion-sensing glass slides. To prepare the sensor, a naphthalimide derivative with a terminal double bond was synthesized as a fluorescent carrier. To prevent the leakage of the dye, the carrier is immobilized on a quartz glass plate surface treated with a silanizing agent by UV irradiation. The proposed sensor with visible excitation can be utilized for a copper assay based on fluorescence quenching. The sensor exhibits satisfactory selectivity, reproducibility and response time. The sensing membrane possesses a relatively long lifetime of at least 2 months. Copper ion can be determined in the range between 4.0×10-7- 6.0×10-4 mol/L with a detection limit of 2.0×10-7 mol/L at pH 7.24. The present approach has been demonstrated with the identification of Cu²⁺ in river water sample.5. In chapter 6, a new fluorescent probe for Hg²⁺ based on a rhodamine-thiophene conjugate was synthesized and its fluorescence could be enhanced by the addition of Hg²⁺. The probe shows a high selectivity and sensitivity to Hg²⁺ by forming a 2:1 complex between probe and Hg²⁺ in 50% CH3CN/H2O buffered at pH 6.00. Besides, probe displays a reversible dual chromo- and fluorogenic response toward Hg²⁺ likely due to the chelation-induced ring-openging of rhodamine spirolactam. Hg²⁺ can be determined in the range 5.0×10-8 to 1.0×10-5 mol/L with a detection limit of 2.0×10-8 mol/L. Determination of Hg²⁺ in both tap and river water samples was successfully carried out with the proposed probe.6. In chapter 7, a fluorescent probe for Hg²⁺ based on a rhodamine-coumarin conjugate was designed and synthesized. Probe exhibits high sensitivity and selectivity for sensing Hg²⁺, and increase in fluorescence emission intensity is observed upon binding Hg²⁺ in 50% water/ethanol buffered at pH 7.24. The fluorescence response to Hg²⁺ is attributed to the 1:1 complex formation between probe and Hg²⁺, which has been utilized as the basis for the selective detection of Hg²⁺. Besides, probe was also found to show a reversible dual chromo- and fluorogenic response toward Hg²⁺ likely due to the chelation-induced ring-openging of rhodamine spirolactam. The analytical performance characteristics of the proposed Hg²⁺-sensitive probe were investigated. A wide linear dynamic range of Hg²⁺ from 8.0×10-8 to 2.0×10-5 mol/L was reached with a detection limit of 4.0×10-8 mol/L. The determination of Hg²⁺ in both tap and river water samples was successful.更多还原