DNA Translocations through Nanopores under Nanoscale Preconfinement

Area of Science:

• Nanotechnology
• Biophysics
• Materials Science

Background:

• Solid-state nanopores are crucial for DNA analysis.
• Variations in DNA passage speed cause data inaccuracies.
• Controlling molecular translocation is key for advanced sensing.

Purpose of the Study:

• To minimize passage time variation for DNA translocation through solid-state nanopores.
• To enhance the reliability and efficiency of nanopore-based DNA analysis.
• To investigate the role of nanoscale preconfinement in molecular transport.

Main Methods:

• Fabrication of integrated nanofilter/nanopore devices using silicon nitride membranes.
• Experimental measurements of DNA passage times through the devices.
• Computational simulations to analyze molecular dynamics and transport phenomena.

Main Results:

• Nanoscale preconfinement eliminated pore size dependence of DNA passage time distributions.
• A global minimum in the coefficient of variation for passage time was observed.
• Narrower passage time distributions enabled pore-size-independent DNA length separation.
• Suppression of folded translocations ensured single-file DNA passage.

Conclusions:

• Integrated nanofilters effectively control DNA translocation dynamics in solid-state nanopores.
• The method significantly enhances data acquisition rates for nanopore sensing.
• This approach offers practical advantages for DNA sequencing, genomic mapping, and target detection.