Abstract
The presence and number of CTCs in blood has recently been demonstrated to provide significant prognostic information for patients with metastatic breast cancer. While finding as few as five CTCs in about 1 mL of blood is clinically significant, however, detection of CTCs is currently difficult and time consuming. CTC enrichment is performed by either gradient centrifugation of CTC based on their buoyant density or magnetic separation of epithelial CTC, both of which are laborious procedures with variable efficiency, and these processes may take hours, if not days. Igor Sokolov et al. found that the villous structures of the CTC cell membrane surface is longer than normal cells, which are close to the characteristics length of nano-pillar structure and may be useful for CTC capture. Our work provides a chip based device consisting of nanowires to help on the retention of CTC cells from normal cells. This in situ cell capturing device provides simple control, cheap and high throughput way to enrich CTCs by the higher interaction forces generated between the longer villous nanostructure of CTCs and the nanostructures with designated structure length. While normal blood cells, with much shorter villous on surface, will not have significant retention on the the nanowire. With different incubated time, nanowire chip reach the cancer cell capture rate with 22% and WBCs capture rate with 1.53% at 4 hours incubation；With different length of nanowire, nanowire chip reach the cancer cell capture rate with 1.53% and WBCs capture rate with 26.4% at 14.8 um length .