Molecular formula: C10H14O8N2Na2 2H2O
This is EDTA Disodium salt dihydrate, SUPPLIED IN A RE-SEALABLE DOYPACK.
In industry, EDTA is mainly used to sequester metal ions in aqueous solution. In the textile industry, it prevents metal ion impurities from modifying colours of dyed products. In the pulp and paper industry, EDTA inhibits the ability of metal ions, especially Mn2+, from catalyzing the disproportionation of hydrogen peroxide, which is used in “chlorine-free bleaching.” In a similar manner, EDTA is added to some food as a preservative or stabilizer to prevent catalytic oxidative decoloration, which is catalyzed by metal ions. In soft drinks containing ascorbic acid and sodium benzoate, EDTA mitigates formation of benzene.
The reduction of water hardness in laundry applications and the dissolution of scale in boilers both rely on EDTA and related complexants to bind Ca2+, Mg2+, as well as other metal ions. Once bound to EDTA, these metal centers tend not to form precipitates or to interfere with the action of the soaps and detergents. For similar reasons, cleaning solutions often contain EDTA.
The solubilization of ferric ions near neutral pH is accomplished using EDTA. This property is useful in agriculture including hydroponics, especially in calcareous soils. Otherwise, at near-neutral pH, iron(III) forms insoluble salts, which are less bioavailable.
In shampoos, cleaners and other personal care products EDTA salts are added as a sequestering agent to improve their stability in air.
Laboratory applicationsIn the laboratory, EDTA is widely used for scavenging metal ions: In biochemistry and molecular biology, ion depletion is commonly used to deactivate metal-dependent enzymes, either as an assay for their reactivity or to suppress damage to DNA or proteins. In analytical chemistry, EDTA is used in complexometric titrations and analysis of water hardness or as a masking agent to sequester metal ions that would interfere with the analyses. EDTA finds many specialized uses in the biomedical laboratories, such as in veterinary ophthalmology as an anticollagenase to prevent the worsening of corneal ulcers in animals. In tissue culture EDTA is used as a chelating agent that binds to calcium and prevents joining of cadherins between cells, preventing clumping of cells grown in liquid suspension, or detaching adherent cells for passaging. In histopathology, EDTA can be used as a decalcifying agent making it possible to cut sections using a microtome once the tissue sample is demineralised. EDTA is also known to inhibit a range of metallopeptidases, the method of inhibition occurs via the chelation of the metal ion required for catalytic activity. EDTA can also be used to test for bioavailability of heavy metals in sediments.
Dentists and endodontists use EDTA solutions to remove inorganic debris (smear layer) and lubricate the canals in endodontics. This procedure helps prepare root canals for obturation. Furthermore, EDTA solutions with the addition of a surfactant loosen up calcifications inside a root canal and allow instrumentation (canals shaping) and facilitate apical advancement of a file in a tight/calcified root canal towards the apex. It serves as a preservative (usually to enhance the action of another preservative such as benzalkonium chloride or thiomersal) in ocular preparations and eyedrops.
EDTA is used extensively in the analysis of blood. It is an anticoagulant for blood samples for CBC/FBEs.