叉指微电极器件上的核酸分子超灵敏电检测研究

用电学方法在纳米器件上检测生物分子是一种新兴的检测技术，但是高的背景噪音干扰一直是一个未解决的科学问题。本项目拟通过开展基于硅基质叉指阵列微电极纳米器件的核酸分子超灵敏检测研究;致力于探讨叉指阵列微电极器件微纳界面的可控自组装体系及其与核酸分子的相互作用，及其对核酸分子检测和对分子诊断的影响；设计具有分子识别功能导向的自组装新体系和新技术、构建特异性识别生物标记物的多功能纳米结构。研究电检测方法中普遍存在的噪音干扰问题，从理论上来探索噪音的产生根源和解决的办法。利用新型生物酶（人工酶）体系还原金属离子，实现金属纳米粒子在常温常压条件下的可控及稳定生成，达到消除背景噪音的目的，从而实现对核酸分子的高选择性、超灵敏检测。这项研究因而具有十分重要的理论意义。并在此基础上，采用先进的微加工技术将建立的新方法集成于智能化微阵列中，实现核酸分子的特异性识别和超灵敏检测。

DNA based bio-analysis is important in the fields of molecular diagnostics, environmental and food safety monitoring, pathogen identification, forensic sciences, etc. In this project, we are developing a quantitative and ultra-sensitive electronic biosensor displaying a DNA recognition thanks to the silicon dioxide surface modificated with appropriate molecular probes. For this purpose, a new system and technology of self-assembling monolayer aimed to molecule recognition for specific capture of cancer cells or biomarker molecules of certain cancers would be designed and developed. The detection device lies on interdigitated array microelectrodes, fabricated by using semi-conductor technology; it is activated then by silicon chemistry to form a monolayer of molecules with active groups, which are labile to produce a biologically functional surface. The interactions of PNA-DNA will be also investigated for better selectivity of target biomolecules. In order to reduce the noise interference during the process of electrical detection, a new system of metal ion reduction catalyzed by enzymes or artificial enzymes would be introduced to this interdigitated array microelectrodes biosensor, the advantages of this new system includes the production of metal nanoparticles in a steady and controlled way, under the conditions of room temperature、atomsperic pressure and non-pasterized solvents. By so doing, the fast、high selective and ultrasensitive detection of DNA molecules can be realized, which would be used in disease diagnostics at the molecular level. After integration of this detection device with microfluidic channels, a real time、fast、 in vivo、 high selectivity biosensor for biomarker of certain disease e.g cancer would be achieved.