新型稀土纳米粒子荧光探针的调控制备与光学特性

Exploiting and developing some kinds of new rare earth nanomaterials as fluorescent probes have great scientific and practical significance to perform biological detection and increase fluorescent measurement technique.In this project, we intent to select rare earth polyvanadate as the object of study, and prepare several novel Eu3+-doped nanoparticals as fluorescent probes by hydro/solvothermal synthesis. The effects of process conditions, such as the kinds of templates, the polarity of solvents ,the acidity of solution and the ratio of reagents on the structure and morphology of the LaxVyOz:Eu3+ nanoparticals would be discussed to obtain the optimal experimental parameters. Rational formation mechanism of isomeric LaxVyOz:Eu3+ nanocrystals would be put forward based on experimental datum. Energy transference, transition probability,fluorescence intensity and radiative lifetime of LaxVyOz:Eu3+ nanoparticals would be explored to illuminate their luminescence mechanism. Determination of calcium ion and magnesian ion by using LaxVyOz:Eu3+ nanoparticals as fluorescent probes would be investigated. The correlation of preparation conditions, microstructure and fluorescence would be studied to build a research model and provide experimental basis for follow-up work on designing and developing new-style rare earth fluorescent materials. This project would provide a new synthetic route to fabricating novel rare earth fluorescent probes along with promoting the integration of Chemistry, Materials, Physics and Biology.

研制和开发新型纳米稀土荧光探针对生物标记、提高荧光检测技术具有重要的科学意义和实用价值。本项目选取稀土多钒酸盐作为研究体系，采用水/溶剂热法调控制备新型纳米铕荧光粒子，研究模板剂类型、溶剂极性、溶液酸度、反应物配比等制备条件对其结构和形貌的影响，构建LaxVyOz:Eu3+同质异构体的形成机制；探索纳米铕荧光粒子能量传递、跃迁几率、发光强度及荧光寿命等光学特性，阐明其发光机理，建立光谱数据库；探讨LaxVyOz:Eu3+纳米荧光粒子对Ca2+、Mg2+等离子的探针行为，揭示制备方法、微结构与荧光性能之间相关性的普适性规律，并以此为指导设计合成新型稀土荧光探针提供物质基础和器件原型。本项目将为制备新型纳米稀土荧光材料提供一条新途径，也可促进化学、材料、物理、生物等学科的交叉融合。

研制和开发新型稀土纳米粒子荧光探针对生物标记和检测具有重要的科学意义和实用价值。本项目借助表面活性剂PEG-6000和正丁醇的溶剂化作用，首次合成了四方相LaVO4:Eu3+纳米空心球；通过控制溶液的pH值，调控制备了单斜相LaVO4纳米线，其生长机理基于纳米颗粒的定向粘附作用；采用沉淀转换法制备了多种含氟稀土纳米荧光粒子，提出了相应的晶体生长模型；在水热体系中可控合成了一系列不同形貌（纳米线束、纳米棒、纳米棒阵列、纳米球、纳米柱、纳米梭）的四方相稀土离子掺杂钒酸盐纳米粒子，找到了合成特定形貌四方相LnVO4:Re（Ln=La, Nd, Gd, Ho, Ce, Pr；Re=Eu3+, Er3+）纳米粒子阵列的最佳条件；以LaCl3和NH4VO3为反应源，调节溶液的pH为12，控制La(Eu)/Na2EDTA =1/1.15、Eu3+掺杂摩尔浓度为0.05mol/L、反应温度为180℃时水热反应36 h可以获得发红光棒状t-LaVO4:Eu3+；研究了反应物浓度、掺杂离子量、溶剂、模板剂种类、结构导向剂、溶液酸碱度、反应源及配比、反应温度与时间等制备条件对稀土钒酸盐纳米粒子荧光性能的影响，揭示了制备工艺、微结构与荧光性能之间的构效关系；初步研究了LaVO4:Eu3+的探针行为，结果表明其对Ca2+、Mg2+无机离子有很好的检测能力。这些研究结果为新型稀土荧光纳米粒子的合成、稀土钒酸盐荧光纳米粒子的生物应用提供了实验基础和借鉴作用。