Aptamer-based microfluidic device for isolation of circulating tumor cells

The paper presents the design of a microfluidic device for capturing circulating tumor cells, a method for immobilizing aptamers on the surface of the chip reaction chamber, and an algorithm for controlling flows in microchannels. It was shown that the maximum efficiency of aptamer immobilization was achieved by treating the chip surface with a 50% aqueous-alcoholic NaOH solution. In addition, it was found that the most number of tumor cells of the MCF7 culture attached on the surface coated with aptamers at low flow rates of less than 2 $\mu$l/min. It was noted that immobilized tumor cells are capable of being retained by aptamers at flow rates of up to 200 $\mu$l/min.