Agarderivatives for chromatography, electrophoresis and gel-bound enzymes. IV. Benzylated dibromopropanol cross-linked sepharose as an amphophilic gel for hydrophobic salting-out chromatography of enzymes with special emphasis on denaturing risks.

The preparation of benzylated covalently cross-linked Sepharose 2B is described. Such gel was analyzed for its degree of substitution, and gels with three different degrees of substitution were used in chromatographic experiments with dextranase, alpha-amylase, lactate dehydrogenase, alpha-chymotrypsin and trypsin. Yields and chromatographic patterns for different eluting systems were determined. It was found that gradients combining an increase in ethylene glycol concentration with a decrease in salt concentration gave better results than did pure salt gradients. No denaturation was observed for dextranase or alpha-amylase, but the other enzymes tested were partly denatured. The most severe denaturation was observed for lactate dehydrogenase desorbed from the highest substituted gels, although the enzyme was highly active in the adsorbed state. The results and the use of amphophilic gels are discussed.