Stable single walled carbon nanotube-streptavidin complex for bio-recognition

A novel method is described for preparing single walled carbon nanotube (SWNT)−streptavidin complexes via the biotin−streptavidin recognition. The complex shows stability in 18 days, strong biotin recognition capability, and excellent loading capacity (about 1 streptavidin tetramer per 20 nm of SWNT). Capturing biotinylated DNA, fluorophores, and Au nanoparticles (NPs) on the SWNT−streptavidin complexes demonstrates their usefulness as a docking matrix, for instance for electron microscopy studies, a technique requiring a virtually electron transparent support.