The preparation and properties of ficin chemically attached to carboxymethylcellulose.

1. Purified ficin has been coupled to four CM-celluloses by reaction with their acid azide derivatives. Insoluble products containing 1.8-4.7mg. of ficin/100mg. of product and retaining 8.0-12.0% of the free enzyme's esterase activity have been obtained. 2. The amount of bound ficin in these preparations is dependent on the degree of carboxymethyl substitution of the CM-cellulose to which the ficin is attached. 3. A shift of the alkaline limb of the pH-activity curve of ficin when chemically attached to CM-cellulose has been shown. 4. Only a small loss has been observed in the enzymic activity of these products when stored at 2 degrees for 4 months. They are more resistant than free enzyme to heat denaturation. 5. Columns of CM-cellulose-ficin have been packed. The degree of hydrolysis of perfused substrate has been measured for different flow rates through the column. 6. The properties of these derivatives have been discussed.