Insulin purifcn - by partition chromatography on crosslinked dextran gel

摘要

Process for purification of insulin and insulin derivatives by subjecting to partition chromatography on an epichlorohydrin-crosslinked dextran gel, the OH groups of which are for the most part alkylated, in an aqueous-organic solvent system contg. (a) 4-5C alcohols and (b) 1-3C carboxylic acids and/or ammonia or an organic base having a pKa value of ca 5.1-11. The procedure enables both natural and synthetic insulin to be freed from ballast substances, even when these are present in considerable excess in crude synthetic insulin. Even small differences in physical properties are sufficient for the separation to be successful; thus, insulin can be smoothly separated from des-phenylalanine-B1-insulin. The separation is particularly smooth when applied to insulin derivatives with different degrees of acylation, e.g. mono-, di- and tri-acyl-insulins. The new procedure avoids the need for adding urea, and high rates of throughput can be achieved (40 cm. x 2 m. column permits 400-500 g. of insulin to be purified in 24 hrs.).