目前，外周血循环肿瘤细胞（CTCs）检验手段十分有限，无法满足临床诊疗过程中的需求。本项目拟用经济、快速的电化学方法解决CTCs检验技术难题。在前期工作中，申请人对绿色经济、生物亲和性良好的石墨相氮化碳（g-C3N4）进行了系统研究，证明其是构建电化学生物检测方法的潜在理想材料。在本研究中，申请人拟利用g-C3N4的特殊材料结构，改进化学剪裁、光催化等材料修饰、复合技术，深入研究石墨相氮化碳/金属纳米颗粒复合材料的可控制备方案并探讨相关机理。在此基础上，以复合材料作为执行捕捉、识别CTCs的核心功能元件，在电极表面搭载离子传感通道，以金属离子为信使分子，通过模拟生物免疫应答过程，建立灵敏、可靠、特异性高的CTCs快速检测方案。同时，建立特异性CTCs表面抗原响应信号识别体系，对外周血中的CTCs进行初步分型，为最终实现外周血CTCs检测在临床诊断、治疗中的常规化应用提供思路。

For now, there are very limited methods for the clinical detection of circulating tumor cells (CTCs) in peripheral blood. The situation cannot satisfy the demand of clinical diagnosis and treatment. This study intends to solve the problems of CTCs determination with electrochemical methods, which has the advantages such as economical, rapid and so on. In the preliminary research, the applicant have systematically studied a green material of graphite carbon nitride (g-C3N4), which is an economy and bio-affinity material and proved as an ideal candidate for fabricating electrochemical bioassay method. Here, combined with the unique material structure of g-C3N4, the applicant intends to improve chemical cleavage, photo-catalysis and other material modification methods to controllably prepare g-C3N4/metal nanoparticle composite. On this basis, the composite is used as the key component for capturing and recognizing CTCs. Meanwhile, an ion sensing channel would be built on the surface of the composite modified electrode, and metal ion would work as the messenger molecule to establish a sensitive, fast and specific CTC electrochemical detection method by simulating the biological immune response process. Moreover, a signal recognition system based on the specific surface antigen of CTCs would be fabricated to classify CTCs preliminarily. Finally, this study aim to provide some ideas for the routine application of peripheral blood CTCs detection during the clinical diagnosis and treatment.