基于核酸适配体的朊蛋白电化学/压电传感研究

Prion diseases, a group of lethal neurodegenerative diseases, arise from the functional defects of the cellular prion protein when cellular prion protein undergoes some conformation rearrangement and the scrapie prion protein is formed.Because there are no effective therapeutic methods for the patients who have already catched a prion disease,the early diagnosis of prion disease based on the fast and sensitive detection of the scrapie prion protein is very important in the mornitoring of the epidemic spreading and effective therapy of prion disease.Here, baed on the specific binding property of the related aptamer to prion protein,and the special structure (a hydrophobic inner cavity and a hydrophilic outer surface) and molecule recognition property of cyclodextrin,the novel electrochemical biosensors for fast and sensitive determination of prion protein (especially scrapie prion protein) will be developed according to the single/dual electrochemical signals. On the other hand, based on the advantages of piezoelectric sensors in real-time monitoring of the surfacial/interfacial performance,it is explored to real-time monitor the conformation rearrangement process of the cellular prion protein. The obtained results will have promosing applications in the early diagnosis and forewarning of prion disease,the fast screening and studying of the related promoting factors and inhibitors, and the pathological study of prion disease.

朊病毒病是一类致死的神经系统退行性疾病,由细胞型朊蛋白经构象转变形成致病型朊蛋白导致细胞型朊蛋白功能缺陷而引起。由于对已经确诊为朊病毒病的患者目前尚无有效治疗方法，因此，基于致病性朊蛋白灵敏、快速检测的朊病毒病早期诊断在监控该疾病流行传播、以及在永久性脑损伤发生前进行有效治疗等方面具有重大意义。本项目基于核酸适配体对朊蛋白的特异性设别作用、环糊精独特的"内疏水外亲水"结构特点与分子识别性能，发展基于单/双电化学信号传感的快速、高灵敏、可再生的朊蛋白电化学传感器，实现朊蛋白,特别是致病性朊蛋白的灵敏检测；同时，基于压电传感技术在提供表/界面行为实时、原位和动态多维信息方面的优势，探索实时监测细胞性朊蛋白向致病性朊蛋白的转变过程。通过本项目研究，为朊病毒病的早期诊断、预警和相关促进因子与抑制剂等的快速分析筛选和研究建立强有力的新分析方法，同时为朊病毒病的相关病理研究提供支撑。

本项目开展了朊蛋白核酸适配体的选择及相关DNA链的设计与优化、环糊精功能化及其在电极表面修饰、朊蛋白电化学/光电化学传感平台构建及检测性能的电化学/压电/光电化学表征等研究，并优化了环糊精在电极表面聚合固定的相关参数；发展了基于氧化石墨烯/硫堇、CoOOH-硫堇、钴-钴普鲁士蓝类似物等纳米(复合)材料和血晶素/G-四联体DNA酶等为信号放大因子、核酸适配体/抗体为识别单元的朊蛋白电化学传感器；发展了基于核酸适配体对朊蛋白的特异性识别作用、环糊精独特的“内疏水外亲水” 结构特点与分子识别性能的朊蛋白双信号电化学传感平台；发展了基于环糊精空腔堵塞效应的核酸适配体基朊蛋白电化学和光电化学传感器；发掘新型半导体体系，调控相关导带、价带以实现能级匹配，发展了基于光电流方向高效转换的新型朊蛋白光电化学传感策略。相关研究构建了一系列新型朊蛋白电化学/光电化学传感平台，实现了朊蛋白的灵敏、高选择性检测。本项目所发展的传感材料及电化学/光电化学传感策略在朊病毒病的早期诊断与预警、环境污染物监测、生物分析和药物研究等方面具有广阔应用前景。