【作者】 黄小花；

【导师】 蔡青云；

【作者基本信息】 湖南大学 ， 分析化学， 2017， 硕士

【摘要】 上转换纳米材料作为一种非常重要的稀土发光材料,可以将长波长近红外光转换成短波长紫外或可见光。上转换发光纳米材料具有显著的优势,如:发射带窄,毒性低,化学稳定性和光稳定性好,较强的组织穿透深度,并且没有生物样品的自发荧光干扰(噪声),对生物样品的损伤较少,这些独特的反Stokes发光性质,使得上转换纳米材料在太阳能电池、安全标记、生物成像、药物输送与释放、检测等方面具有很好的应用优势。以β-NaYF4为基质的稀土上转换纳米材料,是目前应用最广泛、发光效率最高的材料。目前,合成的大多数β-NaYF4上转换发光纳米材料具有疏水性的表面,在实际应用中存在着在水中分散性差和生物相容性差等问题,成为进一步发展的阻碍。用合适的方法来修饰和改善上转换纳米材料,具有很大的挑战。另一方面,以上转换发光纳米材料为核心,经过表面修饰后再与其他有机染料进行有机复合,以满足在不同领域的应用,也是当前需要解决的一个问题。本论文通过合成上转换发光纳米粒子,开发出能检测金属Cu2+的上转换发光纳米复合探针,主要包括如下内容:1.以β-NaYF4为基质的上转换发光纳米材料的合成及其表面修饰目前,β-NaYF4是发光效率最高的上转换基质材料之一。本论文中,通过水热法,以 β-NaYF4 为基质,掺杂 Yb3+/Er3+/Gd3+、Yb3+/Ho3+/Gd3+、Yb3+/Tm3+/Gd3+,合成了发光性能优异的上转换发光纳米棒。合成的以β-NaYF4为基质的上转换发光纳米棒,平均直径为17nm,平均长度为109nm,六方相,大小形状较为均一。掺杂 Yb3+/Er3+/Gd3+,Yb3+/Ho3+/Gd3+,Yb3+/Tm3+/Gd3+后,在 980 nm 连续波激光器激发下有不同的上转换发光,其发光颜色包括红光、绿光、蓝光。并对合成的β-NaYF4:Yb,Er,Gd采用油包水的反相微乳液法进行了二氧化硅表面修饰,增强了其在水中的分散性和生物相容性,便于以后更好地应用于分析检测中。(第2章)2.基于发光共振能量转移的有机染料TSPP修饰的上转换纳米探针对细胞裂解液中Cu2+的检测应用我们制备了一种Cu2+响应的有机染料TSPP修饰的上转换发光纳米复合探针:β-NaYF4:Yb,Er,Gd@SiO2-TSPP。这种纳米探针是基于上转换发光纳米材料与有机染料之间高效的发光共振能量转移(LERT)过程,以β-NaYF4:Yb,Er,Gd@SiO2上转换纳米材料作为能量给体,TSPP-Cu2+络合物作为能量受体。TSPP-Cu2+络合物的形成导致了该纳米探针在545 nm处的上转换发光淬灭,并且基于545 nm的发光强度相对659 nm处的变化来检测Cu2+。在Cu2+浓度为5 μM-0.16 mM的范围内获得线性响应,通过计算得出检测限为2.16 μM。因为制备的β-NaYF4:Yb,Er,Gd@SiO2-TSPP在水中具有良好的分散和生物相容性,能高选择性的检测细胞裂解液中的Cu2+。通过测定在Hela细胞裂解液中加标Cu2+浓度,得出回收率范围为98%～102%,相对标准偏差低于5.0%。(第3章)更多还原

【Abstract】 As a very important rare earth luminescent material,upconversion luminescence nanoparticles(UCNPs)can convert long wavelength near infrared light into short wavelength ultraviolet or visible light.UCNPs have significant advantages,such as narrow emission band,low toxicity,good chemical stability and light stability,strong tissue penetration depth,no spontaneous fluorescence interference(noise)of biological samples,and less damage to biological samples.These unique anti-Stokes properties make the upconversion nanomaterials a useful application in solar cells,safety markers,biological imaging,drug delivery and release,and detection.The rare earth upconversion nanomaterials with β-NaYF4 as the matrix material are the most widely used materials with the highest luminous efficiency.At present,most of the synthesized P-NaYF4 upconversion luminescence nanomaterials have hydrophobic surfaces,and there are water solubility and biocompatibility problems in practical applications,which is an obstacle to further development.It is a great challenge to modify and improve the upconversion nanomaterials in a suitable way.On the other hand,the upconversion nanomaterials as the core,after surface modification and then combine with other organic dye to meet the application in different areas,which is a problem that needs to be solved.In this paper,an upconversion luminescence nanocomposite structure for the detection of Cu2+ was developed by synthesizing upconversion luminescence nanoparticles.We carry out the study in the following aspects:1.Synthesis and surface modification of upconversion luminescence nanoparticles with p-NaYF4 as matrix.At present,β-NaYF4 as the matrix material is the most efficient method for the synthesis of upconversion luminescence nanomaterials.In this paper,the upconversion luminescence nanoparticles with excellent luminescent properties were synthesized by hydrothermal reaction,doping Yb3+/Er3+/Gd3+,Yb3+/Ho3+/Gd3+,Yb3+/Tm3+/Gd3+ with p-NaYF4 as the matrix.The upconversion luminescent nanorods with P-NaYF4 matrix is uniform with average diameter of 17 nm and the average length of 109 nm.After doping Yb3+/Er3+/Gd3+,Yb3+/Ho3+/Gd3+,Yb3+/Tm3+/Gd3+,upconversion luminescent nanorods have different luminescence under the excitation of 980 nm continuous wave laser.The emission color includes red,green and blue.The synthesized β-NaYF4:Yb,Er,Gd was encapsulated with a layer of ultrathin silica through a water-in-oil reverse microemulsion strategy to enhance its dispersion in water and biocompatibility so that it can be better used in analytical testing.(in chapter 2)2.Organic dye TSPP modified upconversion luminescence nanoparticles with high efficiency luminescence resonance energy transfer for the detection of Cu2+ in cell lysatesWe synthesized a Cu2+ responsive organic dye TSPP modified upconversion luminescence nanoprobe,β-NaYF4:Yb,Er,Gd@SiO2-TSPP.The nanoprobe composed of β-NaYF4:Yb,Er,Gd@SiO2 upconversion luminescence nanorods and Cu2+-reactive organic dye TSPP.The nanosensor is based on the high efficiency luminescence resonance energy transfer(LERT)process between the upconversion luminescence nanorods and the organic dye,in which β-NaYF4:Yb,Er,Gd nanorods worked as the energy donor and Cu2+-responsive TSPP as the acceptor.The formationof the TSPP-Cu2+ complex resulted in the upconversion quenching of the nanoprobe at 545 nm and the detection of Cu2+ based on the change in emission intensity at 545 nm to 659 nm.A linear response was obtained in the range of Cu2+ concentration of 5μM to 0.16 mM,and the detection limit was calculated to be 2.16 μM.Because the prepared β-NaYF4:Yb,Er,Gd@SiO2-TSPP has good dispersion in water and biocompatibility,which can be highly selective detection of cell lysates Cu2+.The analysis of Cu2+ in biological systems was evaluated by the determination of Cu2+spiked in Hela cell lysates with recoveries ranging from 98%to 102%and RSD below 5.0%.(in chapter 3)更多还原