Sephadex® is a commercially produced branched homopolysaccharide. It contains alpha-glycosidic linkages at carbons 2, 3, 4, and 6. The degree of cross-linking at those carbons can be controlled, yielding holes within the molecule of known size. What method can use such a molecule?

Gel exclusion chromatography

Explanation:

Sephadex is a commercially produced branched homopolysaccharide. It contains alpha-glycosidic linkages at carbons 2, 3, 4, and 6. The degree of cross-linking at those carbons can be controlled, yielding holes within the molecule of known size. This homopolysaccharides can be used in gel columns as porous beads for gel exclusion chromatography.

Gel exclusion chromatography separates molecules from a mixture according to their sizes. Sephadex is used in this process as beads that have tiny “tunnels" in them that each have a precise size. The size is called an exclusion limit which means that any molecule above a certain molecular weight will not fit into the tunnels.