Sephadex

Sephadex is a trademark for cross-linked dextran gel. It is normally manufactured in a bead form and most commonly used for gel filtration columns. By varying the degree of cross-linking, the fractionation properties of the gel can be altered.

These highly specialized gelfiltration and chromatographic media are composed of macroscopic beads synthetically derived from the polysaccharide, dextran. The organic chains are cross-linked to give a three dimensional network having functional ionic groups attached by ether linkages to glucose units of the polysaccharide chains.

Available forms include anion and cation exchangers, as well as gelfiltration resins, with varying degrees of porosity; bead sizes fall in discrete ranges between 20 and 300µ.