A Practical laboratory Preparation of Avidin Concentrates for Biological Investigation

1. Preparation of avidin concentrates by precipitation of the active fraction during a 2-day static dialysis (in distilled water) of a 1%saline extract of an acetone coagulation of dried egg white solution at pH 5.1 has been described. 2. The activity of these preparations (1.5 units/mg) averages 20% that of “pure” avidin 8.0 units/mg) and the yield is about one g of such material from 800 g of dried egg white. 3. About 100 1b of dried egg white has been processed by the method described.