Regulating the transport of DNA through biofriendly nanochannels in a thin solid membrane.

Channels formed by membrane proteins regulate the transport of water, ions or nutrients that are essential to cells' metabolism. Recent advances in nanotechnology allow us to fabricate solid-state nanopores for transporting and analyzing biomolecules. However, uncontrollable surface properties of a fabricated nanopore cause irregular transport of biomolecules, limiting potential biomimetic applications. Here we show that a nanopore functionalized with a self-assembled monolayer (SAM) can potentially regulate the transport of a DNA molecule by changing functional groups of the SAM. We found that an enhanced interaction between DNA and a SAM-coated nanopore can slow down the translocation speed of DNA molecules and increase the DNA capture-rate. Our results demonstrate that the transport of DNA molecules inside nanopores could be modulated by coating a SAM on the pore surface. Our method to control the DNA motion inside a nanopore may find its applications in nanopore-based DNA sequencing devices.