新型光电传感器的构建及应用
发布时间：2018-09-05 09:04
【摘要】：光电化学(PEC)生物传感是将光电化学技术与生物识别相结合而发展起来的新的传感方法,该技术背景信号低、灵敏度高、装置价格低廉。目前,PEC生物传感已成为生物分析领域中一门重要的分析技术。本论文用不同的光电活性材料构建了高灵敏的PEC生物传感器件,并实现了对生物分子如半胱氨酸、DNA等灵敏检测。第一章综述了PEC传感技术,对PEC传感器的基本工作原理及其构建过程进行阐述。另外,针对不同的检测对象,对PEC传感器进行了分类,最后介绍了一下本论文的主要工作。第二章制备石墨烯-硫化镉掺锰纳米复合物,并构建了半胱氨酸PEC传感器。石墨烯比表面积较大,负载更多硫化镉,而且石墨烯-硫化镉掺锰纳米复合物能够有效提高光生电子-空穴分离效率,增强光电流。由实验结果可知,该纳米复合物对半胱氨酸具有优良的检测性能。第三章利用无机-有机纳米复合物敏化结合λ核酸外切酶(λ-Exo)循环剪切放大作用,实现对DNA的检测。在目标DNA存在条件下,互补DNA/目标DNA双链中的互补DNA可被λ-Exo剪切,释放出目标DNA,其再次与互补DNA杂交,从而起到目标DNA循环放大的效果。而残余的互补DNA可以与无机-有机纳米复合物标记的探针DNA进行互补,从而实现对电极进行共敏化。这种双信号放大传感器的构建,为癌症DNA的检测提供了新的超灵敏分析平台。第四章构建了基于酶循环剪切、链扩增和酶催化反应的信号放大DNA光电传感器的构建。首先电极上电还原氧化石墨烯,后修饰硫化镉纳米晶以及硫化锌,然后固定捕获DNA,在含有目标DNA,发卡DNA,λ-Exo的溶液中孵育时,循环剪切反应发生,输出的DNA链与捕获DNA互补,随后在溶液中通过链式扩增进一步放大,最后通过生物素-亲和素作用连接上ALP酶,进行催化放大。结果表明,构建的PEC传感器能对目标DNA进行超灵敏检测。
[Abstract]:Photochemical (PEC) biosensor is a new sensing method which combines photochemical technology with biometric identification. It has low background signal, high sensitivity and low cost. At present, PEC biosensor has become an important analytical technique in the field of biological analysis. In this paper, highly sensitive PEC biosensor devices were constructed using different photoactive materials, and the sensitive detection of biomolecules such as cysteine PEC was realized. In the first chapter, the PEC sensor technology is reviewed, and the basic working principle and construction process of PEC sensor are described. In addition, PEC sensors are classified for different detection objects, and the main work of this thesis is introduced. In chapter 2, graphene-cadmium sulphide-doped manganese nanocomposites were prepared and cysteine PEC sensors were constructed. The specific surface area of graphene is larger and the loading of cadmium sulfide is more. Moreover, the nano-composite of graphene and cadmium sulfide doped with manganese can effectively improve the efficiency of photoelectron hole separation and enhance photocurrent. The experimental results show that the nanocomposite has good detection performance for cysteine. In chapter 3, the detection of DNA was realized by sensitizing the inorganic and organic nanocomposites and lambda nucleic acid exonuclease (位 -Exo) cyclic shearing amplification. Under the condition of the existence of target DNA, the complementary DNA in the double strand of complementary DNA/ DNA can be cut by 位 -Exo, and the target DNA, can be hybridized with complementary DNA again, so that the target DNA can be cyclically amplified. The residual complementary DNA can complement the probe DNA labeled by inorganic-organic nanocomposites, so that the electrode can be co-sensitized. The construction of the dual signal amplification sensor provides a new hypersensitive analysis platform for cancer DNA detection. In chapter 4, the DNA photoelectric sensor based on enzyme cyclic shearing, chain amplification and enzymatic catalytic reaction was constructed. After electroreduction of graphene oxide and modification of cadmium sulfide nanocrystalline and zinc sulfide on the electrode, cyclic shear reaction occurs when DNA, is incubated in a solution containing the target DNA, hairpin DNA, 位 -Exo, and the output DNA chains complement the captured DNA. Then the chain amplification was carried out in the solution, and the ALP enzyme was connected with biotin-avidin to catalyze the amplification. The results show that the constructed PEC sensor can detect the target DNA with hypersensitivity.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP212
本文编号：2223819
[Abstract]:Photochemical (PEC) biosensor is a new sensing method which combines photochemical technology with biometric identification. It has low background signal, high sensitivity and low cost. At present, PEC biosensor has become an important analytical technique in the field of biological analysis. In this paper, highly sensitive PEC biosensor devices were constructed using different photoactive materials, and the sensitive detection of biomolecules such as cysteine PEC was realized. In the first chapter, the PEC sensor technology is reviewed, and the basic working principle and construction process of PEC sensor are described. In addition, PEC sensors are classified for different detection objects, and the main work of this thesis is introduced. In chapter 2, graphene-cadmium sulphide-doped manganese nanocomposites were prepared and cysteine PEC sensors were constructed. The specific surface area of graphene is larger and the loading of cadmium sulfide is more. Moreover, the nano-composite of graphene and cadmium sulfide doped with manganese can effectively improve the efficiency of photoelectron hole separation and enhance photocurrent. The experimental results show that the nanocomposite has good detection performance for cysteine. In chapter 3, the detection of DNA was realized by sensitizing the inorganic and organic nanocomposites and lambda nucleic acid exonuclease (位 -Exo) cyclic shearing amplification. Under the condition of the existence of target DNA, the complementary DNA in the double strand of complementary DNA/ DNA can be cut by 位 -Exo, and the target DNA, can be hybridized with complementary DNA again, so that the target DNA can be cyclically amplified. The residual complementary DNA can complement the probe DNA labeled by inorganic-organic nanocomposites, so that the electrode can be co-sensitized. The construction of the dual signal amplification sensor provides a new hypersensitive analysis platform for cancer DNA detection. In chapter 4, the DNA photoelectric sensor based on enzyme cyclic shearing, chain amplification and enzymatic catalytic reaction was constructed. After electroreduction of graphene oxide and modification of cadmium sulfide nanocrystalline and zinc sulfide on the electrode, cyclic shear reaction occurs when DNA, is incubated in a solution containing the target DNA, hairpin DNA, 位 -Exo, and the output DNA chains complement the captured DNA. Then the chain amplification was carried out in the solution, and the ALP enzyme was connected with biotin-avidin to catalyze the amplification. The results show that the constructed PEC sensor can detect the target DNA with hypersensitivity.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP212
【参考文献】
相关硕士学位论文 前2条
1 朱桦;基于半导体纳米材料的标记型光电化学免疫传感[D];南京大学;2016年
2 韩丽;基于不同传感策略构建的光电化学生物传感器[D];南京邮电大学;2015年
，本文编号：2223819
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