Ethylenediamine Tetraacetic Acid is a polyamino carboxylic acid hexadentate ligand.
Ethylenediamine tetraacetic acid (EDTA) is a calcium chelator used to eliminate inhibition of enzyme catalyzed reactions due to traces of heavy metals. For use as an anticoagulant, disodium or tripotassium salts of EDTA are most commonly used. EDTA prevents platelet aggregation and is therefore the preferred anticoagulant for platelet counts. It is an inhibitor of metalloproteases and metal-activated proteases. It acts as a chelator of the zinc ion in the active site of metalloproteases, but EDTA can also inhibit other metal ion-dependent proteases such as calcium-dependent cysteine proteases. EDTA interferes with biological processes which are metal-dependent. It is a buffer component.