Plasminogen: purification from human plasma by affinity chromatography

Plasminogen was prepared from human plasma by affinity chromatography on L-lysine-substituted Sepharose. Thirty milligrams of plasminogen, with a specific activity of 100 caseinolytic units (Committee on Thrombolytic Agents) per milligram of nitrogen, were obtained from 340 milliliters of plasma. This corresponds to over 200-fold purification from plasma. Disc-gel electrophoresis at pH 8.3 indicated seven distinct bands, all of which contained activity.