Development of an aptamer-functionalized molecular recognition gating membrane targeting a specific protein on the basis of the aggregation phenomena of DNA–PNIPAM

Abstract

We developed a molecular recognition gating membrane by grafting a conjugate polymer comprising of aptamer and poly(N-isopropylacrylamide) (PNIPAM) in porous substrate pores. Thrombin-binding aptamer forms double-stranded DNA (dsDNA) with anchor DNA conjugated to PNIPAM. dsDNA is dissociated to single-stranded DNA by the thrombin recognition of the aptamer, and this transformation varies charge state around PNIPAM and induces PNIPAM aggregation. Grafting of the DNA-conjugated PNIPAM to membrane pores can enable the membrane pores to open by PNIPAM aggregation; thus, the pores are controlled by thrombin recognition. In this study, we examined PNIPAM aggregation due to thrombin recognition in a linear polymer system. Next, we characterized the opening and closing behavior of the membrane and proved the concept of gating membrane.