Centrifugal filtration

You can concentrate and/or change buffers for protein, RNA and DNA samples via centrifugal filtration. Filters typically have a specified molecular weight cutoff. All molecules with molecular weight greater than the cutoff will be retained and all molecules with molecular weight less than the cutoff will flow through. Hence, this method can in some cases be used for purification as well.

See

Centrifugal filtration/Nucleic acids

Centrifugal filtration/Protein