Detecting DNA Translocation through a Nanopore using a van der Waals Heterojunction Diode

Area of Science:

• Nanotechnology
• Materials Science
• Biophysics

Background:

• Solid-state nanopore sensing aims for out-of-plane electrical control of DNA during translocation for base-by-base sequencing.
• Two-dimensional (2D) heterostructures offer atomic precision for constructing out-of-plane electronics, ideal for sensing membranes.

Purpose of the Study:

• To demonstrate a novel nanopore architecture for out-of-plane electrical sensing and control of single DNA molecules.
• To explore the use of 2D heterojunctions as electrical sensing membranes for biomolecule translocation.

Main Methods:

• Fabrication of a vertical 2D heterojunction diode using p-type WSe2 on n-type MoS2.
• Characterization of rectified interlayer tunneling currents and ionic transport modulation.
• Concurrent detection of DNA translocation using ionic and diode currents.

Main Results:

• Demonstrated a WSe2/MoS2 heterojunction diode exhibiting rectified interlayer tunneling currents modulated by ionic potential.
• Showcased reciprocal rectification of ionic transport by the heterojunction potential.
• Achieved concurrent detection of DNA translocation and a 2.3-fold electrostatic slowing of translocation speed.
• Utilized encapsulation layers for robust operation and preserved spatial resolution of the 2D heterointerface.

Conclusions:

• Established a new paradigm for out-of-plane electrical sensing and control of single biomolecules using 2D heterostructures.
• The developed nanopore architecture enables precise manipulation and detection of DNA during translocation.
• This work paves the way for advanced DNA sequencing technologies.