Disodium edetate dihydrate
[CAS# 6381-92-6]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic sodium
• Name: Disodium edetate dihydrate
• Synonyms: Ethylenediaminetetraacetic acid disodium salt dihydrate; EDTA disodium salt dihydrate
• Molecular Formula: C₁₀H₁₄N₂Na₂O₈.2(H₂O)
• Molecular Weight: 372.23
• CAS Registry Number: 6381-92-6
• EC Number: 613-386-6
• SMILES: C(CN(CC(=O)[O-])CC(=O)[O-])N(CC(=O)O)CC(=O)O.O.O.[Na+].[Na+]

Properties

• Melting point: 252 °C
• Water solubility: soluble

Safety Data

• Hazard Symbols: GHS07;GHS08 Warning
• Risk Statements: H302-H312-H315-H319-H332-H335-H373-H412
• Safety Statements: P260-P261-P264-P264+P265-P270-P271-P273-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P317-P319-P321-P330-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H302
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	4	H312
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Eye irritation	Eye Irrit.	2B	H320
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Specific target organ toxicity - single exposure	STOT SE	3	H336

Discovery and Applications

Disodium edetate dihydrate, commonly known as EDTA disodium salt or EDTA-Na2·2H2O, is a chemical compound with the formula C10H14N2Na2O8·2H2O. It appears as a white crystalline powder and is highly soluble in water. Disodium edetate is a chelating agent, meaning it can form stable complexes with metal ions, which is one of its most significant properties.

The discovery of disodium edetate dates back to the 1930s when the chemist Frederick J. Koenig synthesized ethylenediaminetetraacetic acid (EDTA) for the first time. EDTA was initially developed for its ability to bind metal ions, particularly calcium and magnesium, leading to its early applications in medicine and industrial processes. The disodium salt form of EDTA, which is more soluble and easier to handle, became prominent in the following years, especially after its commercial production began in the 1950s.

Disodium edetate dihydrate is primarily used in various applications, especially in medicine, agriculture, and analytical chemistry. In medicine, it serves as a chelating agent for treating heavy metal poisoning, such as lead and mercury. By binding to these toxic metals, disodium edetate facilitates their excretion from the body, reducing toxicity and promoting recovery. The compound has been used in chelation therapy for conditions like lead poisoning and is also employed in certain cardiovascular procedures to manage calcium levels.

In agriculture, disodium edetate dihydrate is used to improve the bioavailability of micronutrients in soil. It helps prevent the precipitation of metal ions, ensuring that essential nutrients such as iron, zinc, and manganese are more readily available to plants. This application is crucial for enhancing crop yields and ensuring soil health, particularly in regions with nutrient-deficient soils.

In analytical chemistry, disodium edetate is widely utilized as a complexing agent in various titrations, particularly in determining metal concentrations. Its ability to form stable complexes with metal ions makes it invaluable for analytical procedures, allowing for accurate quantification of metals in various samples. Disodium edetate is also employed in laboratory settings for sample preservation, particularly in biological assays, as it prevents the contamination of samples with metal ions that could interfere with experimental results.

Moreover, disodium edetate dihydrate has applications in the cosmetic industry, where it acts as a stabilizing agent and preservative. It helps prevent the degradation of active ingredients by binding to metal ions that could catalyze unwanted reactions, thereby enhancing the shelf life and efficacy of cosmetic formulations.

Despite its numerous applications, safety considerations are essential when using disodium edetate. Although it is generally regarded as safe when used appropriately, it can cause adverse reactions in some individuals, particularly those with hypersensitivity to chelating agents. Therefore, it is crucial to adhere to recommended guidelines for dosage and application.

In summary, disodium edetate dihydrate is an important chemical compound with a rich history of discovery and diverse applications across multiple fields, including medicine, agriculture, and analytical chemistry. Its unique chelating properties continue to make it a valuable tool in both scientific research and practical applications, underscoring its relevance in contemporary chemistry and industry.

References

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DOI: 10.1007/bf00462142

1960. Omega chrome green BLL: A new analytical reagent. Fresenius' Zeitschrift für analytische Chemie, 173(1).
DOI: 10.1007/bf00465405

2024. Electrochemical sensing platform for detection of heavy metal ions without electrochemical signal. Microchimica Acta, 191(5).
DOI: 10.1007/s00604-024-06334-z