Lipid Modification of Carbon Nanotubes

Detergents have been used for simple solubilization of SWNTs in aqueous solution. Ionic detergents such as SDS will coat the nanotube surface and expose the negatively charged sulfonate groups to the surrounding aqueous environment, thus allowing SWNT dispersion in aqueous 

The following protocol for the activation of Tween 20 with CDI and its subsequent use in modifying a carbon nanotube and coupling an affinity ligand is based on the method of Chen et al. (2003). 

Add 4 g of CDI with mixing and react for 1 hour at room temperature. 

Precipitate the CDI-activated Tween 20 by the addition of ethyl ether, and then isolate the precipitate using centrifugation or filtration. Redissolve the precipitated product in DMSO and repeat the precipitation process two more times to insure removal of excess reactants and reaction by-products. After the final precipitation, dry the isolated precipitate overnight in vacuo to remove remaining solvent. 

Suspend the SWNTs in 1 percent (w/w) CDI-activated Tween 20 solution in water using sonication and allow the detergent molecules to bind for 30 minutes at room temperature. 

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