For the preparative separation of fullerenes, chromatography
methods have usually been employed. However, the separation
efficiency has been a problem.
The COSMOSIL Buckyprep is a packed column designed
especially for the preparative separation of fullerenes by HPLC.
The analytical column size offers large load ability equivalent to
the mass preparative columns of conventional C18
packings. Thus, the mass preparative separation becomes possible
with the use of an analytical HPLC system. Since the COSMOSIL
Buckyprep column employs chemically bonded silica phase, no
special operation techniques are required
Material
characteristics
COSMOSIL BUCKYPREP
Silica gel
high purity porous spherical silica gel
Average particle size
5µm
Average pore size
approx. 120Å
Specific surface area
approx. 300m²/g
Stationary phase
3-(1-pyrenyl)propyl group
End capping treatment
near-perfect treatment
Carbon content
approx. 17%
Suggested solvents
Toluene:
Recommended for most cases as the eluent. Chlorobenzene:
When you need to shorten the separation time, use of chlorobenzene
may be effective. Fullerenes higher than C70 are eluted
in a shorter time. 1,2,4-Trichiorobenzene:
It can be used as the washing solvent for higher fullerenes
adsorbed on to the packings. For washing the column, inject 3ml of
1,2,4-trichlorobenzene to a 4.6mmI.D. x 250mm column and 50ml to a
20mmI.D. x 250mm column after every operation. n-Hexane:
When a higher resolution is required, use of n-hexane may be
effective. However, the separation time may be prolonged. Use it
with toluene (toluene/n- hexane=80/20) if necessary. Comparison of separation efficiency Since the retentivity
of fullerenes on C18 packings is generally weak, the
capacity of C18 columns is exceeded when 70µl (175µg)
sample is injected to a 4.6mmI.D.×250mm column. However, the
COSMOSI L Buckyprep retains fullerenes strongly and can
accommodate 2500µl (6.25mg) of the sample without seriously
degrading the separation. Thus, the capacity of the COSMOSIL
Buckyprep columns are 35 times higher than the C18
packings, and preparative separation can be performed by 4.6mm
columns without a preparative HPLC system
