多元化功能核酸纳米机器的构建及其癌症诊疗一体化应用研究

Cancer is a leading cause of mortality worldwide, and its incidence is still on the rise. Although there are many anticancer drugs in clinical trials or on the market, due to the lack of a full understanding of cancer cells, some treatments also have adverse side effects. If the drug system can detect intracellular tumor markers at the same time of treatment, it will be helpful to investigate the treatment mechanism of anticancer drugs. In view of this, the project is aim to construct a multi-functional nucleic acid nanomachine integrating functions of drug delivery and cell imaging, based on the structural or comformational changes of functional nucleic acid probes modified on the surface of gold nanoparticles. The morphological structure of the multi-functional nucleic acid nanomachine is characterized by transmission electron microscopy and atomic-force microscopy. The effects of surface DNA density and particle size of gold nanoparticles on drug loading and fluorescence quantitative analysis are investigated. Furthermore, taking tumor cells as research object, the fluorescence imaging system of intracellular tumor markers is established to monitor the drug release and anti-tumor effect in real-time, so as to provide new technical support for biomedical analysis.

癌症是世界范围内引起死亡的主要原因，其发病率还在不断上升。尽管目前已有很多抗癌药物在临床实验中或上市生产，但由于缺乏对癌细胞充分的了解，治疗的同时往往会产生严重的副作用。如果药物体系在治疗的同时，还能对细胞内肿瘤标志物进行分析检测，将有助于研究药物的治疗机理。鉴于此，本项目拟将金纳米粒子与多种功能核酸结合，基于金纳米粒子表面修饰的功能核酸探针结构或构象的变化，构建集载药功能和成像功能于一体的多元化功能核酸纳米机器。对其形貌结构进行表征，研究金纳米粒子表面的DNA密度及粒径大小对多元化功能核酸纳米机器载药量和荧光定量分析的影响。进一步以肿瘤细胞为研究对象，建立细胞内肿瘤标志物的荧光成像分析系统，对药物的释放进行实时跟踪以及监测药物的抗肿瘤治疗效果，为生物医学分析提供新的技术支持。

为了解决癌症诊疗过程中肿瘤标志物监测所面临的诸多问题，本项目利用金纳米粒子的光学特性，结合核酸适配体、DNA酶、G-四链体、i-motif等功能核酸优异的分子识别性能，设计和构建了多种基于功能核酸的光学生物传感体系，实现了多种肿瘤标志物的高灵敏和特异性检测，为癌症的早期诊断和治疗等研究领域提供有效的分析手段和技术支撑。与此同时，扩展功能核酸的应用领域，并结合CRISPR-Cas在基因编辑、信号放大等方面的特性，构建功能核酸调控的CRISPR-Cas12a传感平台，用于抗肿瘤药物的筛选分析。通过上述工作的开展，申请人以第一/通讯作者在Analytical Chemistry，Sensors and Actuators: B Chemical，Analytica Chimica Acta等期刊上发表SCI论文10篇，其中影响因子大于5.0的论文6篇；以第一发明人申请发明专利2项，其中授权1项。