EDTA

(noun)

Ethylenediaminetetraacetic acid, widely abbreviated as EDTA is a polyamino carboxylic acid and a colorless, water-soluble solid widely used for its role as a hexadentate ligand and chelating agent, i.e. its ability to "sequester" metal ions such as Ca2+ and Fe3+.

Related Terms

Examples of EDTA in the following topics:

  • Chelating Agents

    • The effect increases with the number of chelate rings, so the concentration of the EDTA complex, which has six chelate rings, is much higher than a corresponding complex with two monodentate nitrogen donor ligands and four monodentate carboxylate ligands.
    • Use of disodium EDTA instead of calcium EDTA has resulted in fatalities due to hypocalcemia.

  • Withdrawing Blood

    • The most likely additive to cause trouble is EDTA, which will affect the coagulation time assays and by chelating some of the metal ions may interfere with some of the biochemistry results (especially potassium).
    • Thus EDTA samples should be drawn last, in most cases, and plain tubes should be drawn first.
    • The purple tube contains EDTA, an anticoagulant, and is typically used for a complete blood count.

  • Reactions of Coordination Compounds

    • The EDTA molecule has six different donor atoms that form the complex.

  • Complete Blood Count

    • A phlebotomist collects the sample, drawing the blood into a test tube containing an anticoagulant (EDTA, sometimes citrate) to stop it from clotting.

  • Physical Characteristics and Volume

    • Two tubes of EDTA-anticoagulated blood.

  • Components of Blood

    • Two tubes of EDTA-anticoagulated blood.

  • Blood Plasma

    • Two tubes of EDTA-anticoagulated blood.

  • Food Preservation

    • .), and disodium EDTA.

  • Coordination Number, Ligands, and Geometries

    • A classic example of a polydentate ligand is the hexadentate chelating agent EDTA, which is able to bond through six sites, completely surrounding some metals.