A new purification procedure is introduced, which uses the advantages of co
lumn chromatography and vacuum filtration. Potassium polyacrylate is used a
s stationary phase. This method is based on the idea that the size of the e
xisting cavities in the polymer increases during a swelling process in dist
illed water. The cavities are big enough to entrap the nanoparticles, but a
llow for a free movement of nanotubes and bundles.