纳米金传感器是近年来研究的热点课题之一，但已报道修饰的纳米金多为二维分布，灵敏度低，难于满足环境与生物样品中农残及神经递质类目标物的检测要求。课题组首次报道了采用未功能化DNA分子构建三维纳米金传感器，灵敏度大大提高，但各层修饰膜之间结合机制尚不清楚。为了进一步提高灵敏度，研讨结合机制，本研究拟采用高度有序的DNA分子构建三维纳米金传感器，通过计算DNA分子与纳米金结合热力学常数、电极覆盖度等参数探讨结合机理。阐明传感器膜的结合机制，为建立高灵敏的三维分布纳米金-DNA复合膜传感器检测农残与神经递质类目标物的新体系提供理论依据。根据该传感器特点研制在线微量检测装置。结合微透析技术开展实时在线检测目标物的研究，探寻目标物体内分布规律、代谢机制以及农残对神经递质浓度变化的影响关系，为临床检测及神经毒物的毒害机制研究提供先进、可靠的技术手段。

The biosensor modified with gold nanoparticles (GNPs) has gained an increasing interest in recent years. However, most of the reported GNPs distributed in two dimensionals and their poor sensitivities hardly meet the investigation needs of pesticide residues and neurotransmitters in environmental and biological samples. So, our research group firstly reported a biosensor modified with three-dimensional (3D) GNPs which constructed by nonthiolated DNA molecules. Consequently, the sensitivity increased enormously. But the coalescent mechanism between each monolayers was remained unclear. In order to further improve the sensitivity and study the coalescent mechanism, 3D GNPs modified biosensor was to construct in this research with highly ordered DNA molecules. Combination mechanism is going to be studied by calculating some electrochemical parameters, such as coalescent constant between DNA and GNPs, coverage of electrode surface, etc. After the illustration of coalescent mechanism of each monolayer, a new investigation system for pesticide residues and neurotransmitters is to presented by constructing ultrasensitive biosensor modified with 3D GNPs. According to the characteristics of this modified sensor, the on-line device of micro analysis is also to be investigated. Based on the real-time and on-line research of target with microdialysis technology, distribution rule and metabolizing mechanism of detected object in human bodies and effect of pesticide residues on the concentration of neurotransmitters, advanced and reliable technology is to presented for the research of clinical determination and toxic mechanism of neurotoxins.

纳米金传感器是近年来研究的热点课题之一，但已报道修饰的纳米金多为二维分布，灵敏度低，难于满足环境与生物样品中农残及神经递质类目标物的检测要求。为了进一步提高灵敏度，研讨结合机制，本研究利用非巯基修饰的DNA分子构建三维纳米金传感器，并将石墨烯等材料应用于传感器的构建。通过计算DNA分子与纳米金结合热力学常数等参数探讨了结合机理。阐明传感器膜的结合机制，建立了高灵敏的三维分布纳米金-DNA复合膜传感器检测农残与神经递质类目标物的新体系。根据在线检测的特点研制了微量检测装置。主要研究内容有以下四个方面：①构建了巯基化合与纳米金的复合膜传感器，探讨了成膜机理，在此基础上建立了5-羟色胺（5-HT）、细胞色素 c、尿酸（UA）、百草枯（PQ）、敌草快（DQ）等农残和体液中常存目标物的检测方法，计算了相关的电化学参数。②构建了番红花红/纳米金/DNA相结合的复合膜传感器，建立了5-HT、多巴胺（DA）等神经递质的检测体系，探讨了反应机理。③将石墨烯与DNA、纳米金相结合，构建复合膜传感器，建立了DA、5-HT、PQ等农残和神经递质的测定方法。④设计了容量可调的微量电解池，实现了与微透析取样装置的联用，并申请了专利。