近红外发光双稀土—有机框架材料的设计合成及其荧光温度传感

发布时间：2018-07-26 14:03

【摘要】：温度是生理学和病理学研究的一个重要参数,细胞内大多数生物分子之间的反应过程,例如：细胞凋亡、神经信号传递、离子输运等,都受到温度的影响。相较于传统的接触型温度传感器,如热电偶、水银温度计等,荧光温度传感由于具有非接触、响应速度快、灵敏度高、不易受强的电磁场干扰及可应用于快速移动的物体和小尺寸物体等优势,受到了广泛关注。而基于双发光中心的比例型荧光温度传感由于不会受探针浓度、发光中心的不均匀性、激发光源和探测器的光电漂移等外部因素的影响,具有较高的灵敏度和准确度,是当前的研究热点。本文针对近红外光具有不受生物组织自荧光干扰、对生物组织损伤较少、穿透深等特点,利用金属-有机框架材料可设计性强的优势,引入具有近红外发光特性的双稀土离子,设计合成了三种双金属混合配位的稀土-有机框架材料,开展生理温度附近的比例型荧光温度传感研究。主要研究内容与结果如下：以近红外发光稀土离子Nd3+、Yb3+与有机配体H3BTC(均苯三羧酸)配位,制备了一系列稀土-有机框架材料LnBTC(Ln=Nd, Yb, NdxYbi-x)。在室温条件下对LnBTC(Ln=Nd, Yb, NdxYbi-x)的近红外荧光性能进行研究,发现以Nd3+吸收峰808 nm激发Nd0.054Yb0.946BTC时,该材料同时表现出Nd3+以及Yb3+的特征发射峰；在该波长激发下研究Nd0.054Yb0.946BTC在288～323 K温度范围内的变温荧光光谱,结果显示该材料中Nd3+和Yb3+的发光强度之比(INd/IYb)与温度之间具有较好的线性关系,相对灵敏度达0.830～1.187% K-1,可以实现生理温度荧光传感。以H2BDC-F4(四氟对苯二甲酸)为配体设计合成了一系列近红外发光稀土-有机框架材料LnBDC-F4(Ln=Nd, Yb, NdxYbi-x)。由于配体中以低声子能的C-F键取代C-H键,有效地减弱了对近红外光的淬灭,使得配体可以通过“天线效应”向稀土离子传能使其发光。在配体吸收峰303 nm激发下,LnBDC-F4(Ln=Nd, Yb, NdxYbi-x)发射光谱中均具有相应的稀土离子的特征发射峰,且Nd0.711Yb0.289BDC-F4中Nd3+和Yb3+的特征发光强度之比(INd/1Yb)在60～280 K低温区域内与温度之间具有较好的线性关系,可应用于低温荧光温度传感。此外,在808nm近红外光激发下,纳米尺寸的Nd0.577Yb0.423BDC-F4中Nd3+和yb3+的发光强度之比(INd/IYb)在293～313 K温度范围内与温度呈良好的线性关系,相对灵敏度达0.967-1.201% K-1,表明该材料可应用于生理温度荧光传感。以H3BTB(1,3,5-三(4-羧基苯基)苯)为配体制备了具有较高灵敏度的近红外发光温度传感材料Nd0.866Yb0.134BTB,该材料在303～333 K温度范围内Nd3+和Yb3+的特征发光强度之比(INd/lYb)与温度呈较好的线性关系,且相对灵敏度达2.090～4.755% K-1,远高于Nd0.054Yb0.946BTC和Nd0.577Yb0.423BDC-F4。此外,该材料在水以及生理缓冲液中均较为稳定,且生物毒性也较小,表明该材料在细胞温度传感中具有较大的应用前景。
[Abstract]:Temperature is an important parameter in the study of physiology and pathology. The reaction process between most of the cells in cells, such as cell apoptosis, neural signal transmission, ion transport and so on, is affected by temperature. Compared to the traditional contact temperature sensors, such as thermocouples, mercury thermometers, and so on, the fluorescence temperature sensing is due to Non contact, fast response, high sensitivity, not easy to be affected by strong electromagnetic interference and the advantages of fast moving objects and small size objects, has attracted wide attention. And the proportional fluorescence temperature sensing based on double luminescent center will not be affected by the concentration of the probe, the inhomogeneity of the luminescent center, and the photoelectricity of the light source and detector. The influence of excursion and other external factors, with high sensitivity and accuracy, is a hot spot of research. In this paper, near infrared light is not affected by biological tissue autofluorescence interference, less damage to biological tissue, penetration depth and so on, using the advantages of strong design of metal organic frame materials and the introduction of near infrared luminescence characteristics. Rare earth ions, designed and synthesized three kinds of bimetallic mixed ligand rare earth organic frame materials, and carried out a proportional fluorescence temperature sensing study near the physiological temperature. The main contents and results are as follows: a series of rare earth organic frames are prepared by the coordination of near infrared luminescent rare earth ions Nd3+, Yb3+ and organic ligand H3BTC (benzol three carboxylic acid). LnBTC (Ln=Nd, Yb, NdxYbi-x). At room temperature, the near infrared fluorescence properties of LnBTC (Ln=Nd, Yb, NdxYbi-x) are studied. When the Nd3+ absorption peak 808 nm excite Nd0.054Yb0.946BTC, the material exhibits both Nd3+ and characteristic emission peaks at the same time. Under this wavelength, the temperature is studied at the temperature of 288~323. In the range of temperature changing fluorescence spectra, the results show that the luminescence intensity ratio of Nd3+ and Yb3+ (INd/IYb) has a good linear relationship with the temperature, and the relative sensitivity is 0.830 to 1.187% K-1, and the physiological temperature fluorescence sensing can be realized. A series of near infrared light luminescence is designed and synthesized with H2BDC-F4 (tetrafluoroethyl two methylene acid) as the ligand. Soil organic frame material LnBDC-F4 (Ln=Nd, Yb, NdxYbi-x). Due to the substitution of the C-F bond with the low phonon energy of the C-H bond in the ligand, the quenching of the near infrared light is effectively weakened, so that the ligand can light it through the "antenna effect" to the rare earth ion energy. Under the ligand absorption peak 303 nm, the emission spectra of LnBDC-F4 (Ln=Nd, Yb, NdxYbi-x) The characteristic emission peaks of the corresponding rare earth ions are all of them, and the ratio of the characteristic luminescence intensity of Nd3+ and Yb3+ in Nd0.711Yb0.289BDC-F4 (INd/1Yb) has a good linear relationship with the temperature in the low temperature region of 60~280 K. It can be applied to the temperature sensing of low temperature fluorescence. In addition, the nanometer size Nd0.577Yb0.423 under the near infrared light excitation of 808nm. The ratio of luminescence intensity of Nd3+ and yb3+ (INd/IYb) in BDC-F4 has a good linear relationship with the temperature in the temperature range of 293~313 K, and the relative sensitivity is 0.967-1.201% K-1, indicating that the material can be applied to physiological temperature fluorescence sensing. The near infrared luminescence temperature with high sensitivity is prepared with H3BTB (1,3,5- three (4- carboxy phenyl) benzene) as ligand. Degree sensing material Nd0.866Yb0.134BTB, the ratio of the characteristic luminescence intensity of Nd3+ and Yb3+ at 303~333 K temperature range (INd/lYb) has a good linear relationship with the temperature, and the relative sensitivity is 2.090 to 4.755% K-1, far higher than that of Nd0.054Yb0.946BTC and Nd0.577Yb0.423BDC-F4., and the material is both in water and in the physiological buffer solution. It is stable and has little biological toxicity, which indicates that the material has great application prospects in cell temperature sensing.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O627;TQ422

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