A microfluidic device for isolation of cell-targeting aptamers

This paper presents a microfluidic device for affinity selection and amplification of cell membrane protein-binding strands from a randomized single-strand DNA (ssDNA) oligomer library, thereby isolating specific cell-targeting aptamers. The device consists of the selection and amplification microchambers situated on a temperature control chip. Affinity selection, integrated with cell culturing, of cell-binding ssDNA is performed in the selection chamber; the selected strands are then amplified by bead-based polymerase chain reaction (PCR) in the amplification chamber. Transfer between the selection and amplification microchambers using pressure-driven flow realizes multi-round aptamer isolation on a single chip. Experimental results demonstrate the feasibility of using this device to develop aptamers that specifically bind to target cells.