Description Application EDTA is an inhibitor of metalloproteases, at effective concentrations of 1-10 mM. EDTA acts as a chelator of the zinc ion in the active site of metalloproteases, and can also inhibit other metal ion-dependent proteases such as calcium-dependent cysteine proteases. For use as an anticoagulant, disodium or tripotassium salts of EDTA are most commonly used. The optimal concentration is 1.5 mg per ml of blood. Preparation Note Soluble in water at room temperature up to 1.45 M. The pH of this solution will be approximately 10 to 11 and will be rather viscous.