DNA-guided 3D pathway reconfiguration of composite nanopores for ion transport regulation.

Ion current rectification (ICR) is essential for understanding analyte-driven nanofluid transport within nanopores. However, the rapid flow rates and limited reaction times in this process can impede electrochemical reactions at electrode interfaces, which consequently lead to electrical noise challenges. Here, we propose a simple strategy to enhance the ICR effect and reduce noise interference through the construction of bio/solid composite pores. The composite pores comprise θ-shaped glass pores that have been sequentially modified with 3-glycidyloxypropyltrimethoxysilane (GLYMO), succinic anhydride (SA) and single-stranded DNA. Three-dimensional (3D) biochannels formed from acrylamide-DNA hydrogels are integrated within glass pores. High-density 3D channels and a highly viscous environment can decelerate analyte traversal, thereby establishing a stable reaction environment. Concurrently, acrylamide-DNA hydrogels modulate pore size through cascade reactions triggered by analytes, thereby altering the transport pathways of ion and affecting ICR. Furthermore, we have developed a sensor featuring adjustable ion transport pathways based on this technology. The detection range can be readily expanded to include nucleic acids, proteins, glycans and a multitude of biomolecules through modifying different aptamers.