Bio-Rad Bio-Beads S-X Media - Manual (Page 7)

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umn. If the amount of swelling is unknown, it can be
checked by swelling a known weight of beads and measur-
ing the volume.
After the beads are fully swollen, they are packed into a
chromatographic column and washed with the solvent in
which they were swollen. Normally, the sample is dissolved
and the elution is performed with this same solvent, to pre-
vent swelling or shrinking of the resin during the run. If the
beads swell during the run, a glass column may break.
When the beads are used for the first time, low molecu-
lar weight polystyrene trapped inside the pores of the beads
will tend to cause slow column equilibration. Although
swelling the beads in one of the solvents listed above will
remove some of the low molecular weight polystyrene, sev-
eral column volumes of the running buffer may be necessary
to reach baseline equilibration.
Packing the Column
Metal columns are often used in gel permeation
chromatography, though glass columns offer the important
advantages of visibility of packing and therefore are better
suited.
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