均相DNA杂交电化学生物分子识别技术的研究

The project will focus on the study of directly electrochemically biomolecular recognition through homogeneous DNA hybridization in solution. Compared to traditional DNA electrochemical biosensing technology, this new technology has the improved DNA hybridization efficiency with simplified procedures, and more repeatable and reliable detection results, because it doesn't need to immobilize the DNA probe on the electrode surface. This project will make a breakthrough on the recognition and transformation mechanisms of electrochemical information through homogeneous DNA hybridization, the amplification of electrochemical signal through homogeneous DNA hybridization, and the multi-targets electrochemical detection through homogeneous DNA hybridization. The electrochemical recognition through homogeneous DNA hybridization can be achieved by host-guest molecular recognition, molecular imprinting, self-assembly technique and the electrochemically active DNA molecular beacons. The electrochemical signal amplification of the biomolecular recognition through homogeneous DNA hybridization can be realized by molecular imprinting, cyclodextrin-wrapped magnetic nanoparticles and electrochemically active (or enzyme-wrapped) nanoparticles. Moreover, this project will develop the technology of multi-targets simultaneously electrochemical recognition based on coding array electrodes and single electrode distinguishing multi-markers. Electrochemically biomolecular recognition through homogeneous DNA hybridization will provide a new technology for the early diagnosis of diseases, direct DNA electrochemical recognition of living cells and the detection of real-time electrochemically quantitative PCR.

课题将研究直接在溶液中进行DNA杂交反应的均相DNA杂交电化学生物分子识别新技术。这种识别技术与传统的DNA电化学生物传感技术相比，因为不需要预先将探针DNA固定在电极表面，因此具有操作简便、可提高 DNA 杂交效率、提高检测的重复性和可靠性等优点。课题将在均相DNA杂交电化学信息识别转换、均相DNA杂交电化学信号放大以及多目标均相DNA杂交电化学检测等方面进行系统研究并取得突破。研究将通过主客体分子识别技术、分子印迹技术、自组装技术和电化学活性DNA分子信标等实现溶液中均相DNA 杂交电化学识别检测。通过研究分子印迹和环糊精膜磁性纳米微粒、电化学活性纳米颗粒等技术实现均相DNA杂交电化学分子识别过程的信号放大。研究基于编码阵列电极和单电极多标记物分辨的多目标物同时电化学识别检测。课题研究成果将可为疾病早期诊断、活体细胞直接DNA电化学识别检测和定量实时电化学PCR检测等领域提供新的技术。

课题主要研究内容为：（1）系列研究了基于环糊精、七元瓜环、柱[5]芳烃等超分子的主客体识别作用的均相DNA杂交电化学生物分子识别技术，建立一系列可直接在溶液中进行DNA杂交，无需在电极表面固定的均相DNA杂交电化学生物分子识别新技术；(2)基于超分子的主客体识别作用，分别研究了多环糊精单吡啶钌和多联吡啶钌环糊精超分子的荧光和电致化学发光DNA和多种蛋白的生物传感技术，这些传感技术具有操作简单，无标记等特点，提高荧光和电致化学发光生物传感技术的灵敏度；（3）分别研究了以聚鸟嘌呤和罗丹明类染料分子作为模板分子,实现分子印迹技术均相识别DNA的电化学生物分子识别技术；（4）研究了以DNA超级链结构、双功能化金属复合纳米颗粒和HRP/SiO2纳米颗粒的信号放大策略实现均相DNA杂交电化学信号放大，使DNA检测灵敏度明显提高；（5）研究了利用电化学扫描显微镜构建 DNA 芯片阵列 SECM 电化学检测，首次实现了9种DNA片段的同时电化学检测。课题共发表SCI收录论文16篇，另有3篇SCI论文已投稿审稿中