Dialytic Separation of Bundled, Functionalized Carbon Nanotubes from Carbonaceous Impurities

Abstract

Separating functionalized single-wall carbon nanotubes (SWCNTs) from functionalized amorphous carbon is challenging, due to their polydispersity and similar physicochemical properties. We describe a single-step, dialytic separation method that takes advantage of the ability of heavily functionalized SWCNTs to bundle in a polar environment while maintaining their solubility. Experiments on functionalized SWCNTs were compared with functionalized, C60 fullerenes (buckyballs) to probe the general applicability of the method and further characterize the bundling process. This approach may simultaneously be used to purify a functionalization reaction mixture of unreacted small molecules and of residual solvents, such as dimethylformamide.

The effects of amine-modified single-walled carbon nanotubes on the mouse microbiota

“…7 The NTs had an average length of ~400 nm and an average diameter of 2-3 nm, including adducts ( Figure 1), with an average primary amine density of one amine per 121 carbons (~275 amines per tube) or about one amine for every 1,455 Da. All tubes were solvent exchanged by dialysis 30 into a 25% methanol-H 2 O solution and then frozen before being lyophilized to a brown powder and dissolved into either sterile water or sterile saline for use in this study. pH was then adjusted to ~7.4 using Sigma-Aldrich pH-indicator strips (7.2-8.8 range) and HCl or NaOH.…”