Abstract
Single walled carbon nanotubes (SWCNT) have attracted a great interest due their extraordinary properties that envisage their use for a wide range of applications [reference physical properties]. However, these properties are controlled by the chirality of the SWC-NTs. Unfortunately, the growth processes available to-date produce SWCNTs with different chiralities. Also, the SWCNTs are produced together with a relatively high quantities of impurities such as amorphous carbon and metallic catalyst particles. Indeed, the purification and manipulation remains problematic, hindering some of the possible applications of these materials. In this paper, the purification of SWCNTs with biological polymers is presented. The results shown that DNA and UNA effectively purify SWCNT from the "soot" obtained during the growth process. The results show how effectively total genomic UNA (tgRNA) purifies SWCNT. Atomic force microscopy (AFM) studies reveal how nucleic acids wrap around SWCNTs forming RNA-CNT composites. Moreover, when a RNA-CNT solution is dried on a hydrophilic surface, SWCNTs are found lying or embedded on a self assembled two dimensional UNA network. Using tgRNA is not only a cheap and effective method of solubilising and purifying CNTs but offers a first step towards the self-assembly of CNTs from solution. Furthermore, tgRNA networks could be a convenient method of electrically linking individual RNA functionalised CNTs over a surface which could prove useful for RNA or DNA biosensors.