重金属配合物光电功能材料在生化分析中的应用研究

发布时间：2018-04-19 23:02

本文选题：电化学传感器 + 光致电化学分析　；参考：《青岛科技大学》2017年硕士论文

【摘要】：电化学生物传感器具有操作简单、灵敏度高、消耗低廉等优点,在相关疾病的诊断、环境检测等方面有着非常重要的应用。监测电化学信号最常用的是计时库仑法,它能够定量地测定电活性物质或表面活性物质在电极表面的吸附量,并且可以容易地得到实验数据,信噪比极好。本论文就采用此方法构建了电化学生物传感器用于腺苷的检测。光致电化学作为电化学的一个分支,目前正在逐步的发展。作为一种新型的分析检测方法,它的光信号与电信号是分开的,所以背景信号的干扰比其它方法要小,因此它在分析检测领域的应用将会越来越广泛。光电传感器的灵敏度取决于采用材料的光电转化效率,所以设计开发新型高效光电材料成为目前越来越重要的研究方向。本课题以设计高效的光电材料为出发点,通过引入光敏基团设计合成高效的铱配合物光电材料,研究其光电性质,结合纳米材料的信号放大,来构建高选择性、高灵敏度的光电传感器,用于生物活性分子的检测。主要研究工作包括以下内容:(1)以链置换DNA聚合和滚环扩增(RCA)作为放大手段,构建了高效的免标记电化学生物传感器,用于腺苷的检测。腺苷会引发自催化DNA聚合/剪切过程,同时释放大量的ssDNA。然后这些释放的ss DNA可作为引物启动RCA聚合反应,在电极表面形成长DNA聚合物以吸附大量电活性指示剂Ru(NH3)63+,实现CC的信号放大。这两种放大手段联用使得传感器的灵敏度大大提高,检测限低至0.032 nM,并且它还对不同种类的核苷表现出高度的选择性和良好的重现性。(2)以香豆素-L(C_L)为主配体,4-(2-吡啶基)苯甲醛(hpba)为辅助配体合成了光电材料[Ir(C_L)(hpba)_2]PF_6(Ir-1),并对其进行了紫外可见吸收光谱、荧光光谱及光电性质研究。结果表明,Ir-1在450 nm处有较强的光吸收。以氧气作为电子受体时,光电材料可以产生稳定的还原电流。再分别以氧气、三乙醇胺、抗坏血酸等作为电子供受体,对其信号的影响进行了讨论,通过对比发现,抗坏血酸作为电子供体,开启电压为-2 V时,光电流最大,且暗电流小。将其作为信号物质构建成光致电化学生物传感器,用于检测DNA。在最佳条件下,这种生物传感器检出限低至9.0 fmol L-1(3σ)。(3)以香豆素-6(C_6)为主配体,二吡啶并[3,2-a:2',3'-c]吩嗪(dppz)为辅助配体合成了光电材料[Ir(C_6)2(dppz)]PF_6(Ir-2),并对其进行了紫外可见吸收光谱、荧光光谱及光电性质的研究。研究表明,Ir-2在480 nm处有较强的光吸收。当氧气作为电子受体时,可以产生稳定的还原电流。对比不同偏置电压发现,偏置电压为0 V时,检测到的光电流大,且关光时的暗电流小。分别以氧气、三乙醇胺、抗坏血酸等作为电子供受体,对其信号的影响进行了讨论,通过对比发现,氧气作为电子受体,开启电压为0 V时,光电流最大,且暗电流小。
[Abstract]:Electrochemical biosensor has many advantages, such as simple operation, high sensitivity, low consumption and so on. It has very important applications in the diagnosis of related diseases and environmental detection. The most commonly used method for monitoring electrochemical signals is the time-coulomb method, which can quantitatively determine the adsorption of electroactive substances or surface active substances on the electrode surface, and can easily obtain experimental data. The signal-to-noise ratio (SNR) is excellent. In this paper, electrochemical biosensor was constructed to detect adenosine. Photochemistry, as a branch of electrochemistry, is developing step by step. As a new analysis and detection method, its optical signal and electrical signal are separated, so the interference of background signal is smaller than other methods, so it will be more and more widely used in the field of analysis and detection. The sensitivity of the photoelectric sensor depends on the photoelectric conversion efficiency of the materials, so the design and development of new and efficient optoelectronic materials has become more and more important research direction. Based on the design of high efficiency optoelectronic materials, the high selectivity of iridium complexes was constructed by introducing Guang Min group to design and synthesize high efficiency iridium complex optoelectronic materials, studying its photoelectric properties and combining with the signal amplification of nanomaterials. A highly sensitive photoelectric sensor for the detection of bioactive molecules. The main research work includes the following contents: (1) High efficiency non-label electrochemical biosensor was constructed by using chain displacement DNA polymerization and ring-amplification method as amplification method, which can be used for the detection of adenosine. Adenosine can initiate an autocatalytic DNA polymerization / shearing process and release a large amount of ssDNA. Then these ss DNA can be used as primers to initiate RCA polymerization and form long DNA polymers on the electrode surface to adsorb a large number of electroactive indicator Ru(NH3)63 to amplify CC signal. The combination of these two amplifiers greatly improves the sensitivity of the sensor. The detection limit was as low as 0.032 nm, and it also showed high selectivity and good reproducibility for different nucleosides. UV-Vis absorption spectra, Study on fluorescence spectrum and photoelectric properties. The results show that Ir-1 has strong light absorption at 450 nm. When oxygen is used as the electron acceptor, the photovoltaic material can produce a stable reduction current. The effects of oxygen, triethanolamine and ascorbic acid as electron donor receptors were discussed. It was found that ascorbic acid was the electron donor and the opening voltage was 2 V, the photocurrent was the largest and the dark current was small. It was used as signal material to construct photochemical biosensor to detect DNA. Under the optimum conditions, the detection limit of this biosensor is as low as 9.0 fmol L-1dppz. 3) the main ligand of this biosensor is coumarin -6C6), and the photovoltaic material [IRC62dppz)] PF6Ir-2n has been synthesized and characterized by UV-Vis absorption spectra. Study on fluorescence spectrum and photoelectric properties. The results show that Ir-2 has strong light absorption at 480 nm. When oxygen acts as an electron receptor, a steady reduction current is produced. When the bias voltage is 0 V, the detected photocurrent is large and the dark current is small when the light is turned off. The effects of oxygen, triethanolamine and ascorbic acid as electron donor receptors are discussed respectively. It is found that the photocurrent is the largest and the dark current is small when oxygen is used as the electron receptor and the opening voltage is 0 V.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB34;O657.1

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