Process for purifying insulin and insulin so prepared.

摘要

This invention relates to a process for purifying insulin using a cross-linked dextran gel cation exchanger containing sulfoalkyl or carboxymethyl groups. The process comprises: a) swelling and equilibrating a cross-linked dextran gel cation exchanger containing sulfoalkyl or carboxymethyl groups; b) packing a column with the swollen gel; c) dissolving a partially purified insulin at a concentration in the range of from about 0.05% to about 12%, weight per volume, in an acidic aqueous medium having a pH of from about 2.5 to about 4.5 and containing urea in a concentration of from about 4 to about 8 moles per liter of medium; d) bringing the insulin solution into contact with the column-packed cation exchanger gel; and e) eluting insulin from the cation exchanger gel at a temperature of from about 5 DEG C. to about 25 DEG C. by passing an eluant over the insulin-containing cation exchanger gel, said eluant comprising acidic aqueous medium containing inorganic salt, and said inorganic salt being present in said acidic aqueous medium in a progressively increasing concentration commencing at or below about 0.2 moles per liter and extending to as high as about 0.4 moles per liter.