Nanopore based DNA sensing methods use electrophoresis to drive negatively charged molecules through nanometer sized pores and monitor the change in ionic current to examine the length or sequence of DNA molecules. It is an inexpensive and attractive alternative to traditional sequencing and analysis technologies as it is a label-free, amplification-free, single-molecule approach that can be scaled for high-throughput DNA analysis. Nanopores have been shown to be a versatile platform capable of sensing subtle changes in the structure of biomolecules.

We report the development of robust multilayered graphene-Al2 O3 nanopore platform for sensitive detection of DNA and DNA-protein complexes. Graphene-Al2 O3 nanolaminate membranes are formed by sequentially depositing layers of graphene and Al2 O3 via atomic layer deposition. Subsequently, nanopores were formed in these stacked membranes using an electron-beam sculpting process. The resulting nanopore architecture is mechanically robust and exhibits state-of-the-art low electrical noise. The platform was used for detection of both DNA and protein DNA complexes and showed the ability to differentiate structural changes like folding and protein binding. The structure can also be used for electrostatic potential control at the nanopore surface to guide ionic current and possibly translocation velocity. The combination of simplicity and versatility makes nanopores an attractive platform for medical diagnostic applications and DNA sequencing.