基于链式杂交反应以及新型纳米材料的信号放大策略在痕量外周血循环肿瘤DNA检测中的应用研究

In recent years, the incidence of cancer has been increasing year by year.Circulating tumor DNA(ctDNA) is an abnormal DNA fragment which is released into the blood system after shedding or apoptosis of tumor cells.The detection of ctDNA in blood can be used to detect tumor early.Due to the extremely low levels of ctDNA in the blood, it is urgent to use the signal amplification methodr to realize the ultra-sensitive detection of trace ctDNA. The project intends to build the electrode interface specificity capture probe DNA-ctDNA recognition system, based on hybridization chain reaction (HCR) and nano probe signal output system. Using electrochemical technology as the key detection method, the ultra-sensitive detection of trace ctDNA will be realized, and the detection of ctDNA will be carried out in a thorough study to realize the detection of extremely low concentration of ctDNA in blood. In this project, on the scale of the detection of ctDNA is expected to reach fM detection limit, which provides the corresponding basis for early diagnosis of cancer. Meanwhile, the project provides data support for the tumour stage, transfer and identification, providing information assurance for the selection and improvement of cancer treatment programmes. In the future, this method can be used to promote the early diagnosis of cancer through blood test, and provide strong technical support for the early diagnosis and prognosis of cancer.

近年来，癌症在我国的发病率有逐年增高的趋势。循环肿瘤DNA(ctDNA)是一类肿瘤细胞体细胞DNA经脱落或者细胞凋亡后释放进入血液系统的异常化的DNA片段。通过对检测血液中ctDNA的检测可以实现对肿瘤的早期检测。由于血液中ctDNA的含量极低，为实现痕量ctDNA的超灵敏检查，亟需利用信号放大方法实现信号放大。本项目拟构建电极界面特异性捕获探针DNA-ctDNA识别体系，电极界面基于链式杂交反应(HCR)的无酶信号放大体系及纳米探针的信号输出体系，以电化学技术作为关键检测手段，实现针对痕量ctDNA的超灵敏检测，开展针对 ctDNA的检测方法学的深入研究，实现对血液中极低浓度ctDNA的检测。在本项目中，对ctDNA的检测预期达到 fM 量级的检测限，为癌症的早期诊断提供相应的依据，为肿瘤分期、转移与鉴定提供数据支持，为癌症治疗方案的选择和改进提供信息保障。

循环肿瘤DNA(ctDNA)是一类肿瘤细胞体细胞DNA经脱落或者细胞凋亡后释放进入血液系统的异常化的DNA片段。通过对检测血液中ctDNA的检测可以实现对肿瘤的早期检测。由于血液中ctDNA的含量极低，为实现痕量ctDNA的超灵敏检查，亟需利用信号放大方法实现信号放大。本项目开展了基于链式杂交反应信号放大的ctDNA超灵敏检测方法的研究。首先构建电极界面特异性捕获探针DNA-ctDNA识别体系，基于链式杂交反应的无酶信号放大体系及纳米探针的信号输出体系，以电化学技术作为关键检测手段，实现针对痕量ctDNA的超灵敏检测。相关工作以项目申请书中预定的方案为原型，以高灵敏度、高选择性、低成本、便捷性等为综合考量的指标，进一步完善了检测方案。项目进展顺利，达到了申请时的各项预期目标，取得了较好的成果。共发表学术论文6篇，申请发明专利3项，已授权1项。