Offset configurations for single- and double-strand DNA inside single-walled carbon nanotubes

Area of Science:

• Nanotechnology
• Biophysics
• Materials Science

Background:

• Nanotechnology offers unique molecular properties with potential applications in medicine and electronics.
• Understanding molecular behavior within nanoscale structures is crucial for developing new technologies.

Purpose of the Study:

• To predict the equilibrium offset positions of single-strand and double-strand DNA molecules inside single-walled carbon nanotubes.
• To investigate the influence of carbon nanotube radius on DNA molecule positioning.

Main Methods:

• Applied mathematical modeling utilizing principles of mechanics.
• Employed the 6-12 Lennard-Jones potential function and continuum approximation.
• Calculated potential energy for DNA molecules within varying nanotube radii, considering helical phase angles for double-strand DNA.

Main Results:

• Both single-strand and double-strand DNA molecules exhibit off-axis equilibrium positions within carbon nanotubes.
• The offset distance of DNA molecules from the central axis increases with increasing carbon nanotube radius.
• A simplified analytical expression for potential energy was derived for double-strand DNA at a helical phase angle of π.

Conclusions:

• The study confirms that DNA molecules preferentially position themselves closer to the carbon nanotube wall.
• These findings provide insights into DNA-nanotube interactions, relevant for nanoscale device design.
• The results highlight the importance of nanotube geometry in determining molecular configurations.