Skip to main content

NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.

Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.

U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Attractive Interactions between DNA-Carbon Nanotube hybrids in Monovalent Salts

Published

Author(s)

Ming Zheng, Xiangyun Qiu, Fuyou Ke, Raju Timsina, Constantine Y. Khripin

Abstract

DNA-carbon nanotube (DNA-CNT) hybrids are nanometer-sized, highly-charged, rod-like molecules with complex surface chemistry, and their behaviors in aqueous solutions are governed by multifactorial interactions with both solvent and co-solutes. We have previously measured the force between DNA- CNTs as a function of their inter-axial distance in low monovalent salts where inter-hybrid electrostatic repulsion dominates. The characteristics of DNA-CNT forces were further shown to closely resemble that of double-stranded DNA (dsDNA) in low salts. However, contrasting behaviors emerge at elevated monovalent salts: DNA-CNT condenses spontaneously whereas dsDNA remains soluble. Here we report force-distance dependencies of DNA-CNT across wide-ranging monovalent salt concentrations. DNA-CNT force curves are observed to deviate from dsDNA curves above 300 mM NaCl, and the deviation grows with increasing salts. Most notably, DNA-CNT forces become net attractive above 1 M NaCl, whereas dsDNA forces are repulsive at all salt concentrations. We further discuss possible physical origins for the observed DNA-CNT attraction in monovalent salts, in consideration of the complex surface chemistry and unique polyelectrolyte property of DNA-CNT hybrids.
Citation
Journal of Physical Chemistry C

Keywords

DNA-carbon nanotube hybrids, polyelectrolyte

Citation

Zheng, M. , Qiu, X. , Ke, F. , Timsina, R. and Khripin, C. (2016), Attractive Interactions between DNA-Carbon Nanotube hybrids in Monovalent Salts, Journal of Physical Chemistry C (Accessed October 1, 2025)

Issues

If you have any questions about this publication or are having problems accessing it, please contact [email protected].

Created June 30, 2016, Updated March 17, 2017
Was this page helpful?