Separation Methods based on Molecular Sieving and Ion Exclusion

Abstract

CROSS-LINKED dextran (‘Sephadex’) has been shown to possess properties of a molecular sieve¹. The size limits for effective molecular sieving depend on the degree of cross-linking. Molecules or ions capable of entering the gel phase may be subject to specific interaction with the matrix substance. Thus, for example, when certain aromatic compounds are passed through ‘Sephadex’ columns, a more extensive retardation is found than if the gel acted as a molecular sieve only.