Sonication mediated covalent cross-linking of DNA to single-walled carbon nanotubes

Bridget D. Dolash, Birck Nanotechnology Center, Purdue University
Roya R. Lahiji, Birck Nanotechnology Center, Purdue University
Dmitry Y. Zemlyanov, Birck Nanotechnology Center, Purdue University
Vladimir P. Drachev, Birck Nanotechnology Center, Purdue University
Ronald Reifenberger, Birck Nanotechnology Center, Purdue University
Donald E. Bergstrom, Birck Nanotechnology Center, Bindley Bioscience Center, Purdue University

Abstract

Sonication with nucleic acids has become a standard method for obtaining aqueous dispersions of carbon nanotubes. On the basis of theoretical studies and scanning probe microscopy (SPM) imaging a widely accepted model for DNA association with SWCNT is one in which the DNA binds through non-covalent pi-stacking and hydrophobic interactions. Following the standard procedures established by others to prepare DNA associated single-wall carbon nanotubes (SWCNT), we have determined that sonication generates radical intermediates then form covalent anchors between the DNA and SWCNT. In light of this finding, results from studies on DNA associated carbon nanotubes, need to be more carefully interpreted. (C) 2012 Elsevier B.V. All rights reserved.

Discipline(s)

Nanoscience and Nanotechnology