The high dispersion of DNA-multiwalled carbon nanotubes and their properties.

DNA-wrapped multiwalled carbon nanotubes (MWCNTs) were successfully obtained by a simple sonication treatment method. The obtained materials were characterized in detail by Raman spectroscopy and scanning electron microscopy (SEM). An SEM image showed that MWCNTs were dispersed sufficiently and covered entirely with DNA. This resulted in high aqueous solubility of the products, with a stability of more than several months. The interaction between DNA and MWCNTs was confirmed by Raman measurements and was ascribed to the strong pi-pi interactions between the backbones of DNA and the surface of carbon nanotubes. The cyclic voltammograms showed that the composite exhibited excellent electrochemical properties. Experimental results also revealed that the high dispersion of DNA-assisted MWCNTs presented a better property compared with pristine MWCNTs. This facile method for obtaining water-soluble MWCNTs has great potential application for both bioscience and biotechnology.