Circulating tumor cells(CTCs)present in the blood of patients with non-hematological cancers are accessible sources for diagnosis and monitoring of cancers.By the aid of the ability of the anti-EpCAM antibody to recognize the epithelial cells,microsystem-based technologies provide robust means for effectively detecting CTCs in vitro.Considering the EpCAM expression is down-regulated during epithelial-mesenchymal transition(EMT)process,the amount of CTCs detected based on anti-EpCAM antibody is underestimated.In our study,the A549 cells targeting peptide(A-1 peptide),as the substitute of anti-EpCAM antibody,was introduced to microfluidic chip to capture A549 cells.