Empty fullerenes and several C6O derivatives have been separated by non-aqueous capillary zone electrophoresis for the first time. The separation mechanisms are thought to involve solvophobic association, acid-base chemistry, and anionic complexation. Selectivity improvement was achieved by: using a smaller diameter capillary; increasing the polarity or viscosity of the medium with the addition of organic modifiers; adjusting the solvent composition; and using a tetraalkylammonium salt with a longer carbon chain and at a higher concentration. Mixed electrolyte systems were found capable of further selectivity improvement. Moreover, compounds possessing extended π-systems could provide additional selectivity for resolving the fullerenes in the non-aqueous system. A reasonable precision h...[ Read more ]

Empty fullerenes and several C6O derivatives have been separated by non-aqueous capillary zone electrophoresis for the first time. The separation mechanisms are thought to involve solvophobic association, acid-base chemistry, and anionic complexation. Selectivity improvement was achieved by: using a smaller diameter capillary; increasing the polarity or viscosity of the medium with the addition of organic modifiers; adjusting the solvent composition; and using a tetraalkylammonium salt with a longer carbon chain and at a higher concentration. Mixed electrolyte systems were found capable of further selectivity improvement. Moreover, compounds possessing extended π-systems could provide additional selectivity for resolving the fullerenes in the non-aqueous system. A reasonable precision has also been demonstrated for the method. Our results have established non-aqueous capillary zone electrophoresis as a new and inexpensive separation technique for the analysis of fullerenes.

The isolation of endohedral metallofullerenes from the soot materials has been an important subject of research. In view of this, the potential of using solid phase extraction for the enrichment of endohedral metallofullerenes was investigated. From the APCI-MS, HPLC and LC-MS analyses, it was found that this simple cleanup technique, employing Cl8 bonded silica, could remove a portion of empty fullerenes from a chlorobenzene solution containing empty fullerenes and discandium fullerenes, and there was no indication that the metallofullerene content was reduced significantly. Measures for improving the present method were also suggested.