二硫化钼的合成及其类过氧化物酶特性的研究与应用

发布时间：2018-05-13 02:34

本文选题：MoS_2 + 类过氧化物酶　；参考：《济南大学》2017年硕士论文

【摘要】：天然酶因其具有催化效率高、催化性能专一的优点被广泛应用在医药合成、临床检测、环境监测和农业等各个领域。但由于其不耐酸碱、不耐高温、稳定性不好、提纯繁琐、价格昂贵等不足限制了它的广泛应用。因此,利用化学合成的方法合成一类具有催化性能的类酶来代替这种传统的生物酶非常有必要。进来,随着纳米材料的不断开发和研究,因其具有良好的表面效应、量子尺寸效应被广泛的应用在了各个领域,但是其类过氧化物酶的特性往往被忽略。自从2007年阎锡蕴课题组成功合成了四氧化三铁磁性纳米粒子的类过氧化物酶的特性以来,随后金属氧化物、金属硫化钼、MOF等纳米材料的类过氧化物酶的特性都被相继发现。并且与天然酶相比类酶具有很多优点:催化性能高,稳定性好,合成简单,成本低。基于以上内容,本文主要工作是系统开发和研究不同形貌的MoS_2类过氧化物酶,研究其催化机理,并将其应用在电化学和电化学发光生物传感领域,用于检测肿瘤标志物和寡核苷酸序列的含量。三年来主要开展了以下四方面的研究工作:(1)采用简单的方法合成MoS_2-Au复合物,在过氧化氢存在的条件下,片状MoS_2能够催化氧化TMB变色,证明MoS_2具有类过氧化物酶的性质,它能够催化过氧化氢分解产生稳定的电流信号,并且MoS_2-Au复合物的酶催化活性比MoS_2好,原因是引入了导电性良好的Au NPs,因此,将其应用在免疫传感器上,用于检测CEA的含量。MoS_2-Au复合物用于标记一抗,二抗标记在Ag NPs-GOx的复合物上。产生的电流强度与CEA含量的对数值成线性关系,采用电化学方法可以灵敏检测CEA的含量。此方法操作简单、重现性好、成本低,可用于血清样品中肿瘤标志物的检测。(2)制备具有良好导电性的金-纸工作电极,合成粒径小的MoS_2纳米片,实验证明,和大粒径的MoS_2纳米片相比,其对过氧化氢的催化性能更好,类过氧化物酶的特性更稳定。基于此制备了一个便携式的夹心型免疫传感器,用于测定CA125的含量,该纸芯片免疫传感器可用于临床肿瘤标志物的实时检测,这种操作简单的分析手段在临床诊断有很好的应用前景。(3)将合成的MoS_2纳米片应用在DNA传感器上,在量子点-过氧化氢体系中起到猝灭Cd S/Zn S电化学发光的作用。利用该原理构建电化学发光传感器用于检测寡核苷酸序列的含量,此方法操作简单、灵敏度高、选择性好,可用于血清中DNA含量的检测。MoS_2类过氧化物酶可以广泛的应用在生物技术和基因领域,在临床诊断中具有很好的应用价值。(4)为了增大MoS_2的有效催化比表面积,采用水热法一步合成3D-花状MoS_2,由于有效催化表面积的增加,3D-花状MoS_2的催化活性比片状MoS_2好。基于此性质,构建了一种基于鲁米诺发光试剂的新型检测肿瘤标志物PSA的电化学发光免疫传感器。电化学发光强度与PSA浓度的对数值成线性关系,线性范围是0.001 ng·m L~(-1)~100ng·m L~(-1),检测限低至0.28 pg·m L~(-1)。该MoS_2类酶显著的催化活性使它代替了天然酶用于构建基于酶的分析方法,这种方法可以用于鉴别其他的目标分子。
[Abstract]:Natural enzymes have been widely used in various fields, such as pharmaceutical synthesis, clinical testing, environmental monitoring and agriculture, because of their high catalytic efficiency and catalytic performance. But because of their lack of acid-base, high temperature resistance, poor stability, tedious purification, high price and so on, it has limited its wide application. Therefore, chemical synthesis methods are used. It is necessary to be a class of enzyme like enzymes with catalytic properties instead of this traditional enzyme. With the continuous development and research of nanomaterials, the quantum size effect has been widely used in various fields because of its good surface effect. But the properties of its peroxidase like enzyme are often ignored. Since 2007, Yan Xiyun Since the project team successfully synthesized the properties of the peroxidase of iron oxide magnetic nanoparticles, the properties of peroxidase in metal oxide, molybdenum sulfide, MOF and other nanomaterials have been discovered successively. And compared with natural enzymes, the enzyme class has many advantages: high catalytic performance, good stability, simple synthesis and low cost. Based on the above, the main work of this paper is to develop and study the different morphologies of MoS_2 peroxidase, to study its catalytic mechanism, and to apply it in the field of electrochemical and electrochemiluminescence biosensors to detect the content of tumor markers and oligonucleotide sequences. In the past three years, the following four research work has been carried out. (1) a simple method is used to synthesize the MoS_2-Au complex. Under the presence of hydrogen peroxide, the flake MoS_2 can catalyze the oxidation of TMB. It is proved that MoS_2 has the properties of peroxidase, which can catalyze the decomposition of hydrogen peroxide to produce stable current signal, and the enzyme catalytic activity of MoS_2-Au complex is better than that of MoS_2. The reason is the introduction of the result. Au NPs, which has good electrical conductivity, is applied to the immune sensor to detect the content of CEA content.MoS_2-Au complex for labeling one anti, two anti labeling in Ag NPs-GOx complex. The current intensity is linear with the value of CEA content, and the electrochemical method can detect the content of CEA sensitively. This method is simple to operate. Single, reproducible and low cost can be used in the detection of tumor markers in serum samples. (2) the preparation of gold paper working electrodes with good conductivity and the synthesis of small size MoS_2 nanoscale have proved that compared with the large size MoS_2 nanoscale, the catalytic properties of the hydrogen peroxide are better and the properties of the peroxidase are more stable. Based on this A portable sandwich immunosensor was prepared to determine the content of CA125. The paper chip immune sensor can be used to detect the clinical tumor markers in real time. This simple method of analysis has a good application prospect in the clinical diagnosis. (3) the synthesized MoS_2 nanoscale is applied to the DNA sensor, and the quantum dot - peroxy is used. The chemical luminescence of Cd S/Zn S was quenched in the hydrogen system. The electrochemiluminescence sensor was used to detect the content of oligonucleotide sequence. This method is simple, sensitive and selective, and can be used for the detection of DNA content in serum.MoS_2 peroxisase, which can be widely used in biotechnology and gene. The field has good application value in clinical diagnosis. (4) in order to increase the effective catalytic surface area of MoS_2, 3D- flower like MoS_2 is synthesized by hydrothermal method. The catalytic activity of 3D- flower like MoS_2 is better than that of flake MoS_2 because of the increase of effective catalytic surface area. Based on this property, a new type of Lumino luminescent reagent is constructed. The electrochemiluminescence immunosensor of the tumor marker PSA was measured with a linear relationship between the electrochemiluminescence intensity and the concentration of PSA. The linear range was 0.001 ng. M L~ (-1) ~100ng. M L~ (-1), and the detection limit was low to 0.28 PG m. The method can be used to identify other target molecules.

【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ136.12;O657.1

【相似文献】