Light-Triggered Specific Cancer Cell Release from Cyclodextrin/Azobenzene and Aptamer-Modified Substrate.

Cell adhesion behaviors of stimuli-responsive surfaces have attracted significant attention for their potential biomedical applications. Distinct from temperature and pH stimuli, photoswitching avoids the extra input of thermal energy or chemicals. Herein, we designed a novel reusable cyclodextrin (CD)-modified surface to realize photoswitched specific cell release utilizing host-guest interactions between CD and azobenzene. The azobenzene-grafted specific cell capture agent was assembled onto the CD-modified surface to form a smart surface controlling cell adhesion by light radiation. After UV light irradiation, the azobenzene switched from trans- to cis-isomers, and the cis-azobenzene was not recognized by CD due to the unmatched host-guest pairs; thus, the captured MCF-7 cells could be released. Light-triggered specific cancer cell release with high efficiency may afford a smart surface with significant potential applications for the isolation and analysis of circulating tumor cells.