循环肿瘤细胞（CTCs）在血液中含量极少，但与癌转移密切相关，因此获得一定数量的CTCs成为癌症早期诊断及预后疗效判断最有希望的方法之一。由于CTCs体外捕获技术存在取血量有限导致假阴性率高等缺陷，在线捕获技术成为更有前景的研究领域。针对现有静脉血原位植入在线捕获CTCs技术存在的血液流动快及捕获表面积小导致捕获效率低等不足，本项目提出基于毛细流道束仿生粘性表面的CTCs非植入型在线捕获器的全新思路。即建立体外血液循环回路，将静脉血引入捕获器中实现CTCs在线高通量捕获。其创新性在于模拟癌转移CTCs在血管表面的黏附过程，制备含有E选择素的仿生粘性表面，延长CTCs在材料表面的停留时间，为提高抗体高效捕获CTCs提供保证；通过对毛细流道结构参数的优化，提高捕获器与血液中CTCs的接触表面积和接触时间，进而为提高捕获数量奠定基础。为发展用于癌症早期诊断的CTCs捕获器件提供理论和技术基础。

Circulating tumor cells (CTCs) are extremely rare cancer cells in the bloodstream, which own significant information of related cancer progression and metastasis. Hence, methodological approaches to isolate and detect rare CTCs in the peripheral blood of cancer patients can be used as one of promising technology for early cancer diagnosis and prognosis. However, false-negative results usually occur during in vitro isolation of CTCs due to the limit of the blood volume. On the contrary, in vivo capture of CTCs from a large number of peripheral blood offers the potential applications in both research and clinical fields. Because of the low isolation purity of in vivo CTCs capture techniques caused by both small surface area of implanted materials and high blood flow rate, in this project we propose a novel non-invasive CTCs capture device (CTC-Capturer) using bionic adhesive surfaces of capillary bundles. In vitro a blood circulation circuit is created and the venous blood is guided into the CTC-Capturer to capture CTCs. The advantages of this approach are as follows: i) Inspired by the cancer metastasis of CTCs adhesion on the surfaces of blood vessels, the bionic adhesive surfaces of the capillary bundles are constructed with E selectin to elongate the residence time of CTCs on the surfaces and to further enhance the CTCs capture efficiency. ii) The contacting area/time between the CTC-Capturer and CTCs can be improved through optimizing key parameters of capillary structure, which can provide necessary conditions for the effective CTCs capture. This project aims to provide a novel theory and technology for the development of an efficient CTCs capture devices in early cancer diagnosis.