ABSTRACT：Effective acquirement of highly pure circulating tumor cells (CTCs) is very important for CTC related research. However, it is greatly challenged since abundant white blood cells (WBCs) are always co-collected with CTCs because of nonspecific bonding or low depletion rate of WBCs in various CTC isolating platforms. Herein,we designed a three dimensional (3D) conductive scaffold microchip for highly effective capture and electrochemical release of CTCs with high purity. The conductive 3D scaffold was prepared by dense immobilization of gold nanotubes (Au NTs) on porous polydimethylsiloxane, and was functionalized with CTC-specific biomolecule facilitated by Au-S bond before embedding into a microfluidic device.The spatially distributed 3D macroporous structure compelled cells from linear to chaotic migration and the densely-covered Au NTs enhanced topographic interaction between cells and substrate, thus synergistically improving CTC capture efficiency.Au NTs coated 3D scaffold had good electrical conductivity and Au-S bond was breakable by voltage exposure, so that captured CTCs could be specifically released by electrochemical stimulation while nonspecific bonded WBCs were not responsive by this process, facilitating recovery of CTCs with high purity. The 3D conductive scaffold microchip was successfully applied to obtain highly pure CTCs from cancer patients' blood, demonstrating its promising potential for promoting downstream analysis of CTCs.

DOI：10.1021/acs.analchem.1c00785