The Preparation and Assay of Toxic Proteolytic Products Producing Skin Hemorrhage1

Abstract
Toxic products appearing in the course of pancreatic digestion of fibrin were assayed by measurements of hemorrhages appearing after intracutaneous injection. A 5-point slope ratio assay utilized colorimetric determinations of alkaline hematin released from individual injection sites by incubation in 1[image] NaOH. The potency of both ultrafiltrable and non-ultrafiltrable portions remained high after prolonged pancreatic digestion.