Nanotubes complexed with DNA and proteins for resistive-pulse sensing

ACS Nano. 2013 Oct 22;7(10):8857-69. doi: 10.1021/nn403323k. Epub 2013 Oct 10.

Abstract

We use a resistive-pulse technique to analyze molecular hybrids of single-wall carbon nanotubes (SWNTs) wrapped in either single-stranded DNA or protein. Electric fields confined in a glass capillary nanopore allow us to probe the physical size and surface properties of molecular hybrids at the single-molecule level. We find that the translocation duration of a macromolecular hybrid is determined by its hydrodynamic size and solution mobility. The event current reveals the effects of ion exclusion by the rod-shaped hybrids and possible effects due to temporary polarization of the SWNT core. Our results pave the way to direct sensing of small DNA or protein molecules in a large unmodified solid-state nanopore by using nanofilaments as carriers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA, Single-Stranded / chemistry*
  • Microscopy, Atomic Force
  • Nanotubes / chemistry*
  • Proteins / chemistry*
  • Spectrum Analysis, Raman

Substances

  • DNA, Single-Stranded
  • Proteins