Molecular transport through large-diameter DNA nanopores

Area of Science:

• Biomolecular Engineering
• Nanotechnology
• Synthetic Biology

Background:

• DNA nanotechnology offers precise control over synthetic biomolecular pore geometry and function.
• DNA-based nanopores are emerging as key tools for single-molecule biosensing and synthetic biology.

Purpose of the Study:

• To engineer and characterize a large-diameter DNA membrane channel.
• To investigate its spontaneous insertion into lipid bilayers and its utility in molecular translocation.

Main Methods:

• Fabrication of DNA channels with tunable geometry and hydrophobic functionalization.
• Incorporation into flat lipid bilayer membranes and giant unilamellar vesicles.
• Electrical measurements of conductance and analyte translocation, confocal microscopy, and dye influx assays.

Main Results:

• A large DNA membrane channel (≈4 nm pore diameter) with stable electrical properties was successfully created.
• Spontaneous insertion into lipid bilayers was achieved via hydrophobic functionalization or streptavidin-lipid linkages.
• The channel exhibited Ohmic conductance (≈3 nS) and facilitated electrically driven DNA analyte translocation.

Conclusions:

• Large DNA membrane channels can be readily integrated into lipid bilayers.
• These channels are suitable for single-molecule analysis and hold potential for synthetic biology.
• The ability to form pores in both orientations expands their applicability.