循环肿瘤细胞（CTCs）检测对肿瘤转移的早期诊断、患者预后及疗效评估具有重要意义。由于CTCs数目极少，使得其检测一直受到挑战。前期研究中我们创建了用于CTCs检测的适配子型生物传感器，实现了CTCs快速、特异性的检测，但仍存在灵敏度（32个细胞/mL）不够高和反应体系中粘度及内部应力对结果干扰等问题。为此，本项目拟在前期QCM传感器研究的基础上，引入电化学传感技术，构建新型电化学压电生物传感器（EQCM）检测技术平台，以电化学参数对谐振频率变化进行校正，消除反应体系中粘度及内部应力的干扰。通过滚环扩增与量子点的有机结合建立生物信号级联放大技术，以提高EQCM的检测灵敏度。进一步通过检测热力学和动力学参数，阐明EQCM的液相响应机理，为其在液相检测中的应用奠定理论基础。最终创建一种全新的超灵敏EQCM传感技术平台，实现CTCs的快速高灵敏检测，以期为肿瘤转移的早期诊断及其机制研究奠定基础。

The detection of circulating tumor cells（CTCs）is significant for the early diagnosis, prognosis, and efficacy evaluation of tumer metastasis. The challenge regarding detection is the fact that CTCs are rare events. In order to solve the above problems, our previous study has develpoed an aptamer-based biosensor for detecting CTCs. The CTCs were rapidly and specificlly detected by the aptamer-based biosensor. However, the detection sensitivity（32 cells/mL）was not enough, and the result of biosensor was interfered by the viscosity and internal stress of reaction system. In this study, we want to establish a novel electrochemical quartz crystal microbalance（EQCM）which introduces electrochemical sensor technology to the privious studies established QCM. Thus, the resonance frequency variation could be corrected by electrochemical parameters, and the interference of viscosity and internal stress is eliminated. Furthermore, the rolling circle amplification (RCA) and quantum dots are combined to establish the biological signaling cascade technology in order to improve the detection sensitivity of EQCM. Subsequently, the response mechanism of EQCM in liquid phase will be built by detecting the thermodynamic and kinetic parameters. Finally, a novel ultrasensitive EQCM is established for CTCs detection. The present study aims to provide new method for earlily identifing the tumer metastasis and investigating the mechanisms.