基于核酸－石墨烯纳米偶联物的活细胞荧光成像生物传感新方法研究

Living cell fluorescent imaging sensors are among the frontier technologies for real-time, in situ, visualized and selective detection of intracellular components. This project focuses on the common challenges in living cell fluorescence imaging analysis, such as low intracellular deliverry efficiency, low imaging sensitivity, high biological toxicity, and severe non-specific adsorption. Based on the unique optical, chemical and biological properties of graphene nanosheets, we will combine the versatile molecular recognition functions and flexible signal transduction strategies of nucleic acids to develop novel nanocomposite of graphene and nucleic acids for living cell imaging sensors. We will perform systematic studies on the fundamental issues such as molecular recognition activity, biological stability, intracellular delivery efficiency and signal transduction strategies of the nanocomposites. Then, we can develop generic methods for the construction of fluorescence-activatable graphene-nucleic acid conjugate probes with excellent biological compatibility and stability, high intracellular delivery efficiency, and superb imaging contrast. Based on the nanoconjugate probes, living cell imaging sensors will be developed for highly sensitive and selective detection of the activity and the subcellular distribution of telomerase and dicer, two nucleic acid modifying enzymes with close implication in tumors. These sensor may have great potential as an efficient platform for biomedical researches, clinical diagnostics and drug development.

活细胞荧光成像传感是对细胞内成份进行实时、原位、可视化、选择性检测的前沿技术。本项目拟围绕活细胞荧光成像分析仍面临的探针输送效率低、荧光成像灵敏度有限、生物毒性较大、非特异性吸附较强等瓶颈问题，以纳米石墨烯的独特化学、光学与生物学特性为基础，结合核酸探针丰富的分子识别功能与信号转换策略，系统研究核酸－石墨烯纳米复合物的识别活性、生物稳定性、细胞输送特性、信号转换性能等基础性问题，探索生物相容性与稳定性好、细胞输送效率高、高对比度荧光激活式核酸－石墨烯纳米探针构建的通用方法，并基于核酸－石墨烯纳米偶联物发展新型的活细胞成像生物传感技术。在此基础上，针对恶性肿瘤相关的细胞内端粒酶与Dicer酶的活性检测为目标，提出核酸修饰酶活性与亚细胞分布高灵敏、高选择性的活细胞成像分析新方法，为相关的生物医学研究、临床诊断、药物筛选提供有效的技术平台。

近年来发展的新型纳米材料具有许多独特的物理化学性质，这些性质使得纳米材料尤其适合于生化分析与生物传感。我们基于纳米材料的独特性质，在纳米生物分析、活细胞成像分析以及生物分析的信号放大技术方面开展了较系统深入的研究工作，取得较为突出的研究成果。发表标注基金资助的通讯作者SCI源刊论文33篇，影响因子>5.0的论文18篇，其中包括化学顶级期刊J. Am. Chem. Soc. 2篇（影响因子12.113），Anal. Chem. 3篇，Chem. Commun. 3篇， Nanoscale 4篇， Trac-Trend Anal. Chem.，ACS Appl. Mater. Interfaces, J. Mater. Chem.各1篇，Biosens. Bioelectron. 3篇等。研究成果得到了国内外同行的认可。获得国家自然科学基金杰出青年基金（2015年），教育部新世纪优秀人才支持计划（NCET-11-0121）、湖南省杰出青年基金（12JJ1004）、教育部自然科学奖一等奖（第五完成人）。作为负责人承担了4项国家自然科学基金青年基金和面上项目。