The purification of human fibrinogen

Abstract

I955with plasma proteins, but the fibrinogen was precipitated though in an intractable form.Arising from this, methods have been described for the successive separation of fibrinogen, prothrombin, y-globulin and albumin fractions from human plasma under rigidly aseptic conditions for clinical purposes, using defined quantities of ether with suitable adjustment of pH, ionic strength and temperature (Kekwick, Mackay & Record, 1946; Kekwick & Mackay, 1949; Kekwick & Mackay, 1954).This paper describes the development of a method using ether in the further purification of human fibrinogen.The purity of intermediate fractions and of the final product was assessed by electrophoresis and ultracentrifuge measurements, by the determination of the proportion of the total protein nitrogen which was recoverable in the clot formed with thrombin, and by tests designed to establish the degree of contamination with, or freedom from, plasminogen and plasmin. EXPERIMENTAL MaterialsAll the chemicals used were of analytical reagent quality.Aqueous solutions and buffers were made up in sterile pyrogen-free water and, where necessary, were sterilized by passage through a Seitz filter, or by autoclaving at 20 lb.pressure for 30 min.