Experimental study on single biomolecule sensing using MoS₂-graphene heterostructure nanopores

Area of Science:

• Materials Science
• Nanotechnology
• Biophysics

Background:

• Solid-state nanopores are crucial for single-biomolecule sensing (DNA, proteins).
• Ultra-short translocation times limit detailed biomolecule analysis and applications like sequencing.
• Graphene can impede biomolecule passage, while MoS2 does not significantly hinder translocation.

Purpose of the Study:

• To investigate if combining MoS2 and graphene in nanopores can slow down biomolecule translocation.
• To explore the potential of MoS2-graphene heterostructure nanopores for enhanced single-molecule analysis.
• To analyze the interaction between biomolecules and the MoS2-graphene heterostructure during translocation.

Main Methods:

• Fabrication of sub-10 nm ultra-thin MoS2-graphene heterostructure nanopores.
• Single-molecule level experiments using dsDNA and native protein (Bovine Serum Albumin - BSA).
• Analysis of translocation time, signal length, and signal form during molecule passage.

Main Results:

• MoS2-graphene heterostructure nanopores demonstrated high stability.
• Observed unique signals potentially reflecting BSA shape changes during slow translocation.
• BSA translocation time was extended to over 100 ms.
• Translocation signal characteristics depended on BSA-heterostructure interaction extent.
• Weak BSA-MoS2 interaction increased translocation probability; strong BSA-graphene interaction slowed translocation and altered BSA structure.

Conclusions:

• MoS2-graphene heterostructure nanopores effectively slow down single-biomolecule translocation.
• This approach enables the acquisition of more detailed biomolecular information.
• The findings highlight the potential of these heterostructure nanopores for advanced biomolecular analysis and sequencing.