基于 SECM 的活性氧及氧化应激过程电化学信号分析研究

Reactive oxygen species (ROS) including superoxide anion, hydrogen peroxide, and hydroxyl radical, are excess generated in vivo during oxidative stress processes. The overproduction of ROS may damage the cells and cause cancer, Neurological diseases and Alzheimer’s disease. Due to the lack of effective analysis method for the direct determination of ROS, it is subject to certain restrictions to study the relationship between oxidative stress in living organismsis and related diseases. This program is about the intersisciplinary study between electrochemistry and life science. It focuses on the research of interaction between reactive oxygen species and biological moelcules (include DNA) in oxidative stress processes by means of scanning electrochemical microscopy (SECM). We will establish new methods to detect ROS with high sensitivity and fast response, as well as the evaluation system of oxidative stress damage. Based on this, we will carry out the real-time online detection for ROS that release by the cell itself, and explore the relationshp among the ROS species, oxidative stress and the related disease. After finishing this program, it will provide a platform for the direct determination of ROS in living organismsis, and an important experimental method for investigation the effect of the ROS concentration changes on the cell physiological activities. Furthermore, it will provide the experiment base for the diagnosis of the disease, screening of anticancer and anti-aging drugs.

氧化应激过程中产生的活性氧（ROS）会损伤细胞，有可能引起癌症、神经性疾病、帕金森病等生理病变。由于有效直接测定ROS分析方法的匮乏，生物体内氧化应激状态与相关疾病之间关系的研究受到一定制约。本项目立足于电化学技术与生命科学的交叉研究，以活性氧及氧化应激过程密切相关的生物分子为研究对象，以扫描电化学显微镜(SECM)为手段，致力于氧化应激过程中活性氧与DNA 等生物分子的相互作用机理研究；建立灵敏度高、响应速度快的活性氧检测新方法；建立氧化应激损伤的评价体系。在此基础上，对细胞中的活性氧释放规律进行实时在线检测，探索氧化应激、活性氧物种与引起相关疾病之间的相关性。该项目的完成将为生物体中活性氧的直接检测提供技术平台，为研究活性氧浓度的变化在细胞生理活动中的作用提供重要的实验手段，为疾病的诊断，抗癌抗衰老药物的筛选提供实验基础。

氧化应激过程中活性氧和活性氮（ROS和RNS）的异常表达水平与包括癌症在内的许多疾病有关。基于其有效直接测定方法的缺乏，本项目以氧化应激过程相关的活性氧、活性氮生物分子为研究对象，基于功能化碳基纳米复合材料建立高灵敏、快响应电化学检测新方法，实现对细胞释放活性物的在线检测，为探索氧化应激状态、活性氧变化与生理病理活动之间的相关性提供支持。主要研究内容如下：（1）功能化碳基纳米复合材料构筑电化学传感器的制备及表征；基于新型纳米材料，构建了系列性能优异的电化学传感器，拓展了功能材料在生物传感界面的应用。（2）活性氧、活性氮的电化学分析检测方法的建立及相关动力学研究；结合棉花碳纤维材料及银纳米粒子优势的超灵敏无酶电化学传感器，对超氧阴离子检出限低至2.32×10-15M。有机共轭微孔聚合物构建了电流型传感器，实现了直接监测细胞释放的过氧亚硝基阴离子。（3）模拟氧化应激模式下，活性氧对DNA 等生物分子的损伤及相关机理研究。（4）细胞释放活性氧，活性氮实时检测；新型比率电化学传感器的构建，首次实现了H2O2 和ONOO- 的同时检测.（5）氧化应激模式下，抗氧化剂清除能力的研究。通过本项目的研究为细胞释放活性氧、活性氮的直接检测提供了技术平台，为抗癌抗衰老药物的筛选提供了实验基础，对预防预报重大疾病具有潜在的应用价值。