Bio-Rad Bio-Beads S-X Media - Manual (Page 3)

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Introduction
Bio-Beads S-X beads are a series of porous crosslinked
polystyrene polymers used for gel permeation separations of
lipophilic polymers and low molecular weight, hydrophobic
materials in the presence of organic solvents. These non-
aqueous spherical beads are used in much the same way
aqueous gels are used, except that they are swollen with
organic solvents during the separation.
Technical Description
Bio-Beads S-X beads are neutral, porous styrene
divinylbenzene copolymer beads. The beads in the Bio-
Beads S-X series have exclusion limits from 400 to 14,000
daltons. This range makes them particularly suitable for the
fractionation and separation of low molecular weight organ-
ic polymers and other hydrophobic substances. The amount
of divinylbenzene crosslinkage determines the pore size,
and hence the molecular weight exclusion limit of a particu-
lar gel in this series. The beads are available with crosslink-
ages from 1-12%. Pore dimensions and exclusion limits are
also influenced by the eluant employed; maximal expansion
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