【作者】 李飞；

【导师】 陈野；

【作者基本信息】 哈尔滨工程大学 ， 应用化学， 2009， 硕士

【摘要】 近年来,随着生命科学的不断发展,生物化学分析的应用也越来越广泛。由于荧光光谱的灵敏度高、选择性好,荧光探针技术已经在蛋白质、核酸、细胞检测及免疫分析等方面发挥了重要作用,其中各种荧光稀土纳米颗粒探针则是荧光分析的有力工具。本文采用反相微乳液法制备了掺杂型荧光(Eu、Tb)纳米二氧化硅颗粒,及共价型荧光纳米二氧化硅BHHCT-Eu-SiO2,通过X-射线衍射、红外光谱、荧光光谱等手段对制备物的结构、形态、性质进行了表征。并将BHHCT-Eu-SiO2与氯霉素抗体相连作为荧光探针应用于氯霉素的免疫层析试纸条分析。本文所制备的掺杂型荧光(Eu、Tb)纳米二氧化硅颗粒均为非晶态或极小晶体,EDTA中的羰基与Eu3+(Tb3+)以双齿配位的形式配位,当掺杂元素为Eu时,荧光光谱分析表明,在396nm处没有出现Eu3+的本征激发峰,而在310nm处出现一较强激发峰,表明配合物的激发光谱由配体EDTA吸收能量引起,并将能量传递给Eu3+使之发出特征荧光,在310nm光激发下,发射波长位于615nm处,对应于Eu3+离子电偶极跃迁5D0→7F2,发射光谱中没有出现磁偶极跃迁5D0→7F1表明Eu3+的配合物中稀土离子处于不对称中心；当掺杂元素为Tb时,荧光光谱分析表明,在277-396nm之间有一宽而强的Tb3+离子的激发谱带,240nm处的最强激发峰是由配体EDTA吸收能量,并将能量传递给Tb3+使之发出特征荧光所引起,在240nm光激发下,发射波长位于486nm(5D4→7F6)、544nm(5D4→7F5)、582nm(5D4→7F4)、620nm(5D4→7F3)。掺杂的EDTA-Eu(Tb)与SiO2摩尔比在1：120-1：15之间时,随着EDTA-Eu(Tb)的掺杂量的增加荧光粒子在各发射波长下的最大发射荧光强度均成指数函数增长。荧光粒子BHHCT-Eu-SiO2,激发峰分别位于231nm、274nm、318nm、340nm处,其中231、274和340nm处的激发峰由配体的n(π)→π*跃迁引起,最大激发峰318nm是由配体吸收能量,通过分子间能量传递给Eu3+,使之发出荧光所致,发射光谱中最强发射峰位于615nm(5D0→7F2)处,另外两个弱发射峰位于592nm(5D0→7F1)和649nm(5D0→7F3)处,615nm处发射峰强度远远强于592nm处发射峰,说明荧光探针中Eu3+处于非反演中心。BHHCT-Eu-SiO2-Ab作为荧光探针进行免疫层析试纸条法检测氯霉素时,对氯霉素检测限为10ng/mL,氯霉素琥珀酸盐检测限为1ng／mL,重复性良好,特异性良好,与甲砜霉素、卡娜霉素、磺胺二甲基嘧间无交叉反应。更多还原

【Abstract】 In recent years, with the constant development of life science, biochemical analysis was uesed more and more widely. Fluorescence spectroscopy has high sensitivity and selectivity, so fluorescence probe technology has played an important role in the proteins, nucleic acids, cells and immune detection analysis. Among them, lanthanide-coated nanoparticals probe is a powerful tool.In this paper, fluorescent doped Eu and Tb nano-silica particles were prepared by reverse microemulsion, fluorescent covalent nano-silica BHHCT-Eu-SiO2 was prepared by reverse microemulsion, too. The structure, morphology and the nature of preparing products were characterized by X-ray diffraction, infrared spectroscopy, fluorescence spectroscopy. And BHHCT-Eu-SiO2 was used in detecting chloramphenicol by immunochromatographic strip method.In this paper, fluorescent doped Eu and Tb nano-silica particles are amorphous or very small crystals, the coordination forms of carbonyl in EDTA with Eu3+(Tb3+) is double coordination. When the doping element is Eu, fluorescence spectroscopy analysis shows that the features excitation peak at 396nm was not observed, and the excitation peak appeared at 310nm, it shows that the excitation spectrum of the complex was caused by EDTA absorbing energy and the energy was transfered to Eu3+ which make it issue features fluorescent. With the 310nm of light excitation, the emission wavelength is 615nm. The strong emission band of Eu3+ at 615nm belongs to electric dipole transition 5D0→7F2, as magnetic dipole transition 5D0→7F1 of Eu3+ was not observed, the Eu3+ in the complex was at the asymmetric center. When the doping element is Tb, fluorescence spectroscopy analysis shows that between 277 and 396nm, there is a strong and wide-band excitation, the strongest excitation occurred at 240nm, it was caused by EDTA absorbing energy and the energy was transfered to Tb3+ to make it to issue features fluorescent. With the 240nm of light excitation, the emission wavelength appeared at 486nm(5D4→7F6) 544nm(5D4→7F5)、582nm(5D4→7F4)、620nm(5D4→7F3). When the molar ratio of EDTA-Eu(Tb) and SiO2 was between 1:120 to 1:15, the fluorescence intensity in every emission wavelength will increase with the concentration of Eu(Tb), and the growth is exponential growth.The excitation peaks of BHHCT-Eu-SiO2 appeared at 231nm,274nm,318nm, 340nm, among them the excitation peaks at 231nm,274nm,340nm are caused by n(π)→π* transition of some groups in BHHCT. The strongest excitation occurred at 318nm, it was caused by ligand absorbing energy and the energy was transfered to Eu3+ to make it to issue features fluorescent. With the 318nm of light excitation, the emission wavelength appeared at 615nm(5D0→7F2)、592nm(5D0→7F1)、649nm(5D0→7F3), and 5D0→7F2 transition is much stronger than 5D0→7F1, which indicates that the Eu3+ in the complex is at the asymmetric center. When BHHCT-Eu-SiO2-Ab as a fluorescent probe was used in detecting chloramphenicol by immunochromatographic strip method, the method detection limit of chloramphenicol is 10ng/mL, while chloramphenicol succinate salt is lng/mL. This method has good reproducibility and specificity, it has no cross reaction with thiamphenicol kanamycin sulfamethazine.更多还原