Aptamer-immobilized open tubular capillary column to capture circulating tumor cells for proteome analysis.

Circulating tumor cells hold the key to predicting the prognosis and discovering the therapeutic targets. Herein, we proposed a strategy to develop an aptamer-immobilized open tubular capillary column by which SMMC-7721 human hepatoma cells (SMMC-7721 cells) could be captured with an over 70% of capture efficiency and a 3.0 ± 0.2 of enrichment factor. Owing to the compatibility of the column, the captured cells by the column could be analyzed by LC-MS from protein level and 5 unique proteins of SMMC-7721 cells were identified which could be used as markers to identify SMMC-7721 cells when Jurkat T-leukemia cells (Jurkat cells) were employed as interfering cells. As the key component, the aptamer-immobilized column had the potential to be integrated into the platform for separating, enriching and characterizing rare cells simultaneously.