How Density Gradient Ultracentrifugation Works
The Process
Disperse - Step 1
CNTs are dispersed in aqueous solution using a combination of surfactants. Different surfactants bind selectively to CNTs of different species, thereby augmenting the effective density difference between them.
Seperate - Step 2
The CNT solution is inserted into a density gradient, and the mixture is centrifuged under a very high relative centrifugal field. During centrifugation, the surfactant-encapsulated CNTs migrate to their isopycnic (same density) point in thedensity gradient, resulting in spatial CNT separation.
Fractionate - Step 3
The separated CNTs are isolated using established fractionation techniques.
Package - Step 4
If desired, the surfactants are removed from the separated nanotubes. The separated SWNTs are then characterized and packaged appropriately for sale
