MgO纳米带/BDD电极的制备及多组分同步测定生物传感机制研究

The detection and quantification of electrochemically active compounds such as ascorbic acid (AA), dopamine (DA), uric acid (UA), tryptophan (Trp), and nitrite (NO2-) in biological fluids, such as blood and urine is very important. Their improper level in body leads to various fatal diseases. Therefore, their routine analysis is very important. AA, DA, UA, Trp, and NO2- usually coexist in blood serum. Therefore, the development of a sensitive and selective method for their simultaneous determination is highly desirable for analytical application and diagnostic research. Expand the potential window, accelerate electron transfer, reducing the background current, and improve voltammetric peak separation are efficient approaches to build electrochemical biosensing system for these five substances simultaneous determination. . In this project, the strong adsorption and special surface electron transport properties of MgO nanobelts, wide potential window, low background currents and strong electro-catalytic oxidation characteristics of boron-doped diamond film (BDD) will be utilized to construct a novel electrochemical biosensor based on MgO nanobelts/BDD composite electrode, to achieve simultaneous determination of the above-mentioned five kinds of substances; designed single MgO nanobelts electrode electrochemical detection system to study the dynamic changes in the electrochemical process morphology, electrical and electrochemical the relationship between performance and analyze the electron transfer and electrochemical sensing mechanism; analysis of the synergies mechanism of electro-catalytic oxidation between the MgO nanobelts and the BDD film, combined with the adjustment of the electrolyte environment, improve the sensitivity of the sensing system, to achieve synchronization and trace detection of the five substances in body fluids..

抗坏血酸、多巴胺、尿酸、色氨酸及亚硝酸根这5种物质共存于人的体液内，开发可同步测定这5种物质的高效传感器件，对于疾病的诊断具有重要的实际意义。扩大电势窗、加快电子转移、降低背景电流和实现待测物伏安峰的分离是构建上述5种物质同步测定电化学生物传感体系的有效途径。. 本项目利用MgO纳米带的强吸附及特殊的表面电子传输特性，利用掺硼金刚石膜（BDD）的宽电势窗、低背景电流及强电催化氧化特性，设计基于MgO纳米带/BDD电极的新型电化学生物传感器，实现对上述5种物质的同步测定；而设计单根MgO纳米带为电极的电化学检测系统，研究其在电化学过程中的形貌动态变化、电学和电化学性能之间的关系，分析其电子传输与电化学传感机理；分析MgO纳米带与BDD膜的电催化协同增效机理，再结合电解液环境的调整，提高传感体系的灵敏度，实现上述5种物质的同步痕量检测。

本项目的研究重点是电化学传感器的多组分同步测定生物传感机制。为此，抗坏血酸（AA）、多巴胺（DA）、尿酸（UA）、色氨酸（Trp）及亚硝酸根（NO2-）等体液内共存的电活性物质作为检测对象，通过研究各种新型敏感膜及基础电极对上述分析物的电催化机制，着重分析待测物的定性及定量指标“峰电位”和“峰电流”与传感电极成分及结构的构效关系，由此阐明了多组分同步测定生物传感机制。.首先，采用电子辅助化学气相沉积法在优化了的工艺参数下制备了宽电势窗口、低背景电流的掺硼金刚石（BDD）电极，并采取镍辅助氢/氩等离子体刻蚀工艺制备了多孔BDD电极，通过研究电极与电解液界面间的电荷转移和离子转移动力学，制备了适用于多目标同步检测的BDD传感器电极。.其次，采用直流电弧等离子体喷射化学气相沉积系统在不同工艺下制备了蝌蚪状、纳米带及纳米棒等不同的MgO纳米结构，分析了这些纳米结构的形貌、成分及微结构缺陷，研究了微结构缺陷对电化学响应特性的影响。.再次，开发了多孔Ni/BDD、多孔BDD、MgO纳米带、垂直石墨烯等单独及复合的传感电极，结合每种分析物的前沿分子轨道能级，研究了AA、DA、UA、Trp及NO2-等5种生物分子的同步测定传感机制，构造了同时检测3～5种分析物的检测系统，建立了定量检测模型，对血清内的电活性物质进行了检测。.在本项目的资助下，以第一作者或通讯作者共发表了30篇SCI论文（其中SCI一区论文12篇、SCI二区论文11篇），其中1篇入选了ESI前1%高被引论文，并申报了16项发明专利。