上转换纳米颗粒的合成、修饰及其在免疫试纸条上的应用

发布时间：2018-04-20 16:32

  本文选题：反St(o|)kes发光 + 上转换纳米粒子　； 参考：《湖南大学》2016年硕士论文

【摘要】：自二十世纪90年代末开始,上转换纳米材料的领域不断发展,并逐步变成纳米科学最活跃的研究领域之一。在过去20年里发表的大量上转换纳米材料的论文证明,很多研究团队在这个领域做出了大量努力。上转换纳米材料在近红外光激发下,可以发射出紫外、可见或近红外光,即反Stokes发光。这种独特的发光性质,排除了生物样品的背景荧光和来自生物系统的光散射,因此信噪比高。目前上转换纳米粒子可用于生物标记、光动力学治疗和生物成像等领域。本论文把上转换纳米粒子应用于免疫层析技术,实验结果表明,这在一定程度上提高了免疫层析方法的灵敏性和检测准确性。在论文里,我们详细描述了上转换纳米粒子的合成过程和修饰方法,并把它与免疫层析技术相结合去检测C-反应蛋白。(1)本课题组对上转换纳米材料的合成原本已有较丰富的实践经验,在此基础上,我们合成出两种疏水的上转换纳米粒子,即蓝光NaYF_4:Yb,Tm/NaYF_4和绿光NaYF_4:Yb,Er/NaYF_4。为方便进一步与生物分子偶联,我们把油溶性的两种纳米粒子通过表面配体吸附法,即纳米晶体表面疏水基团和高分子疏水碳链之间的疏水相互作用,使纳米晶体吸附上一种两亲性嵌段高分子。高分子亲水的一端裸露在外面,亲水端丰富的羧基增加了纳米粒子的水溶性,也方便进一步与生物分子偶联。通过透射电镜可以发现,纳米粒子几乎全部包覆上一层约2 nm厚的高分子膜。通过实验验证,证明这种表面修饰法耗时少,全程约30 min,操作简单,且修饰好的纳米粒子在水溶液里不易团聚,就目前来说,是效率较高且较容易的表面修饰方法。(2)免疫层析技术,是基于抗原抗体的特异性识别,通过毛细管虹吸作用,使液体样品在试纸条上横向流动,液体样品里的目标物被分析膜上捕获蛋白捕获,最后通过检测免疫试纸条的检测线的荧光强弱来判断目标物浓度的方法。我们把上转换纳米粒子作为荧光探针应用于免疫层析技术,再检测人体内C-反应蛋白。结果表明,该方法不仅保留了免疫层析试纸条操作简单,经济实惠的优点,而且应用上转换纳米粒子为荧光探针,提高了C-反应蛋白的检测灵敏度和准确性。并且,它可以被用于更多种类的抗原样品的半定量和定量检测中,具有较好的市场应用前景。
[Abstract]:Since the late 1990s, the field of up-conversion nanomaterials has been developing and gradually becoming one of the most active research fields in nanoscience. Papers published over the past 20 years on up-conversion nanomaterials have demonstrated that many research teams have made a lot of effort in this area. The up-conversion nanocrystalline materials can emit ultraviolet, visible or near-infrared light, that is, anti- luminescence, under the excitation of near-infrared light. This unique luminescent property excludes the background fluorescence of biological samples and light scattering from biological systems, so the signal-to-noise ratio (SNR) is high. Up-conversion nanoparticles can be used in biomarkers, photodynamic therapy and biometric imaging. In this paper, the up-conversion nanoparticles were used in immunochromatography. The experimental results show that the sensitivity and accuracy of immunochromatography are improved to some extent. In this paper, we describe the synthesis process and modification methods of up-conversion nanoparticles in detail. And combine it with immunochromatography to detect C- reactive protein. (1) our team has had rich practical experience in the synthesis of up-conversion nanomaterials. On this basis, we have synthesized two kinds of hydrophobic up-conversion nanoparticles. That is, the blue light NaYF4: YbBU Tm / NaYFANG4 and the green NaYFs 4: Yb/ / NaYF4. In order to facilitate further coupling with biomolecules, two oil-soluble nanoparticles were adsorbed by surface ligands, that is, the hydrophobic interaction between the hydrophobic groups on the surface of nanocrystals and the hydrophobic carbon chains of polymers. An amphiphilic block polymer is adsorbed on nanocrystalline crystals. The hydrophilic end of the polymer is exposed to the outside, and the rich carboxyl groups at the hydrophilic end increase the water solubility of the nanoparticles and facilitate further coupling with biomolecules. It was found by TEM that almost all of the nanoparticles were coated with a polymer film about 2 nm thick. The experimental results show that the surface modification method takes less time, takes about 30 mins, is simple to operate, and the modified nanoparticles are not easy to reunite in aqueous solution. It is an efficient and easy surface modification method. It is based on the specific recognition of antigens and antibodies, and makes liquid samples flow transversely on the test paper by siphon action of capillary tube. The target in the liquid sample is captured by the captured protein on the analytical membrane. Finally, the method of judging the concentration of the target material by detecting the fluorescence intensity of the detection line of the immune test strip is presented. We applied up-conversion nanoparticles as fluorescent probes to immunochromatography to detect C-reactive proteins in human body. The results show that this method not only preserves the advantages of simple operation and economical operation of immunochromatographic strip, but also improves the sensitivity and accuracy of C-reactive protein detection by using up-conversion nanoparticles as fluorescent probes. Moreover, it can be used in the semi-quantitative and quantitative detection of more kinds of antigens, and has a good market prospect.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O658.1;TB383.1
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本文编号：1778588