基于新型纳米材料构建的电致化学发光生物传感器的研究

发布时间：2018-04-17 17:34

本文选题：电致化学发光 + 人类免疫球蛋白　；参考：《安徽大学》2017年硕士论文

【摘要】：电致化学发光(ECL)是指在电极表面产生的自由基通过高能电子转移反应形成激发态并发出光的过程。它是电化学和化学发光相结合的新技术,由于其具有灵敏度高、线性范围宽、背景信号低、选择性好等特点,现已成为一种在基础研究和分析应用方面有用的技术。纳米材料因其具有极好的生物相容性、光学及电化学性质已经被广泛应用于生物传感器的构建。本文利用新型纳米材料及其复合材料构建了一系列高灵敏的电致化学发光生物传感器并对其在生物应用领域进行了探讨,主要研究内容如下:1.基于空间位阻和DNA新型分析策略的生物传感器检测人类免疫球蛋白本文构建了一种基于DNA高选择性的电致化学发光(ECL)生物传感器并结合空间位阻效应来检测人类免疫球蛋白(IgG)。在这个研究中,修饰于信号DNA(signaling DNA)上的半抗原体地高辛(Digxin)可以特异性识别目标蛋白并具有强烈的亲附力。这种由于目标物结合导致的空间位阻效应,限制了 signalingDNA与电极表面的互补链杂交,从而导致较低的ECL信号。在最优实验条件下,生物传感器的ECL信号与IgG的浓度成线性比例,具有广泛的线性范围和较低的检出限。这种独特的检测方法不仅简化了检测过程,缩短了时间,提高了检测的灵敏度。2.基于DNA功能化N-C QDs构建的新型电致化学发光传感器检测microRNA本文通过微波辅助水热法合成N-C QDs,该量子点具有较小的粒径和优良的光学性质。基于N-C QDs作为信号标记物并结合着核酸内切酶(Nb.BbvCI)辅助的循环放大技术,一种超灵敏的生物传感器应用于microRNA的检测被构建。首先,连接着量子点的发卡探针1(HP1),辅助探针和microRNA形成Y状结构,核酸内切酶存在时可以识别Y状结构上的特定位点并切割,随后释放microRNA和辅助探针可以参与下一轮的循环,这样将产生大量的连接量子点的中间片段(S1),这些中间片段可以与修饰在电极表面上的发卡探针2(HP2)发生杂交反应从而产生ECL信号。因此,ECL强度将随着microRNA浓度的增加而增加,该传感器线性范围在10 aM～104fM,检出限为10 aM,并显示具有较高的特异性和良好的重现性。3.基于金纳米颗粒功能化的g-C_3N_4复合纳米材料的无标记电致化学发光适配体传感器检测乙酰胆碱酯酶本文使用Au纳米粒子功能化g-C_3N_4纳米复合材料(Au-g-C_3N_4 NH)作为发光体构建了一种免标记的电化学发光(ECL)适配体传感器用于乙酰胆碱酯酶(AChE)的检测。将Au-g-C_3N_4 NH和巯基修饰的AChE适配体分别相继组装于电极表面用于传感器的构造。在目标物AChE的存在下,AChE可以催化基质物硫代乙酰胆碱水解,水解产生的醋酸可以与发光液的共反应剂三乙胺反应导致共反应剂被消耗。因此,ECL信号发生明显的降低。适配体传感器的ECL响应与AChE的浓度成线性比例,显示出较高的灵敏度,线性范围为0.1pg/mL-10ng/mL,检出限为42.3 fg/mL。该适配体传感器有良好的特异性和稳定性,在临床诊断和生物医学技术上具有潜在的应用优势。
[Abstract]:Electrochemiluminescence (ECL) refers to the electrode surface by electron transfer reaction of free radical formation of excited state and emit light. It is a new technology of electrochemistry and chemiluminescence combined, due to its high sensitivity, wide linear range, low background signal, good selectivity, has become a in the basic research and application analysis of useful technology. Nano materials because of their excellent biocompatibility, construct the optical and electrochemical properties have been widely used in biological sensors. This paper constructs a series of highly sensitive electrochemiluminescence biosensor and explore for use in biological applications using nano materials and composite materials, the main research contents are as follows: 1. the steric and DNA model analysis of the strategy of biosensor detection of human immunoglobulin in this paper is constructed based on a DNA highly selective electrogenerated chemiluminescence (ECL) biosensor based on combining the steric effect to the detection of human immunoglobulin (IgG). In this study, modified on the DNA signal (signaling DNA) on the body of digoxin hapten (Digxin) can identify protein specific targets and has a strong Pro adhesvity. This combination leads to the object due to steric effects, limiting the hybridization of complementary strands signalingDNA and electrode surface, which leads to lower ECL signals. Under the optimum conditions, the concentration of ECL and IgG signal of the biosensor is linearly proportional with linear range and low detection limit detection. This unique method not only simplifies the detection process, shorten the time, improve the sensitivity of.2. detection based on DNA model electric functional N-C constructed by QDs chemiluminescence sensor for the detection of microRNA by microwave Assisted hydrothermal synthesis of N-C QDs, the quantum dot has smaller particle size and excellent optical properties. Based on the N-C QDs as the signal marker combined with endonuclease (Nb.BbvCI) auxiliary cycle amplification technology, detection of an ultra sensitive biosensor based on microRNA was constructed. First, connected with the hairpin probe quantum dots (HP1), 1 auxiliary probe and microRNA formation of Y like structures, there can be specific endonuclease recognition sites of Y structure and cutting, then release microRNA and auxiliary probe can participate in the next round of the cycle, the middle segment will produce a large number of connected quantum dots (S1), the the middle fragment can be modified on the electrode surface and the hairpin probe on the 2 (HP2) cross reaction to produce ECL signal. Therefore, the strength of ECL will increase with the increase of microRNA concentration, the sensor is linear in the range of 10 ~ 104 aM FM, the detection limit was 10 aM, and show high specificity and good reproducibility of.3. label free ECL aptamer sensor for the detection of acetylcholinesterase using Au nanoparticles functionalized g-C_3N_4 nano composite material g-C_3N_4 nano composite function of gold nanoparticles based on (Au-g-C_3N_4 NH) as a luminous body construction a label free electrochemical luminescence (ECL) aptamer sensor for the detection of acetylcholinesterase (AChE). Au-g-C_3N_4 NH and thiol modified AChE aptamers were assembled on the surface of the electrode to the sensor structure. The target in the presence of AChE, AChE can catalyze the substrate acetylthiocholine hydrolysis, hydrolysis to produce acetic acid can cause total reaction agent is consumed and coreactant three triethylamine luminescence liquid. Therefore, the ECL signal decreased significantly. The aptamer sensor EC The L response is linearly proportional to the concentration of AChE, showing a high sensitivity, a linear range of 0.1pg/mL-10ng/mL, and a detection limit of 42.3 fg/mL.. The aptamer sensor has good specificity and stability, and has potential application in clinical diagnosis and biomedical technology.

【学位授予单位】：安徽大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.1;TP212.3

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