Iminodiacetic acid


Iminodiacetic acid is the organic compound with the formula HN(CH2CO2H)2, often abbreviated to IDA. A white solid, the compound is a dicarboxylic acid amine (the nitrogen atom forms a secondary amino group, not an imino group as the name suggests). The iminodiacetate dianion is a tridentate ligand, forming metal complexes by forming two, fused, five membered chelate rings.[1] The proton on the nitrogen atom can be replaced by a carbon atom of a polymer to create an ion-exchange resin, such as chelex 100. Complexes of IDA and EDTA were introduced in the early 1950's by Schwarzenbach.[2]

Iminodiacetic acid
Skeletal formula of iminodiacetic acid
Preferred IUPAC name
2,2′-Azanediyldiacetic acid
Other names
2-(Carboxymethylamino)acetic acid
Diglycolamidic acid
  • 142-73-4 checkY
3D model (JSmol)
  • Interactive image
  • CHEBI:24786 ☒N
  • ChEMBL461164 checkY
  • 8557 checkY
ECHA InfoCard 100.005.051 Edit this at Wikidata
EC Number
  • 205-555-4
  • C19911 ☒N
MeSH imnodiacetic+acid
  • 8897
RTECS number
  • AI2975000
  • XQM2L81M8Z checkY
  • DTXSID2027098 Edit this at Wikidata
  • InChI=1S/C4H7NO4/c6-3(7)1-5-2-4(8)9/h5H,1-2H2,(H,6,7)(H,8,9) checkY
  • OC(=O)CNCC(O)=O
Molar mass 133.103 g·mol−1
Appearance Colourless crystals
Density 1.436 g mL−1
log P 1.84
Acidity (pKa) 1.873
Basicity (pKb) 12.124
−933.9–−931.3 kJ mol−1
−1.6430–−1.6406 MJ mol−1
GHS labelling:
GHS07: Exclamation mark
H315, H319, H335
P261, P305+P351+P338
Flash point 178 °C (352 °F; 451 K)
Related compounds
Related alkanoic acids
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references
Structure of an iron(III) bis ida complex.[1]

IDA forms stronger complexes than the bidentate ligand glycine and weaker complexes than the tetradentate ligand nitrilotriacetic acid. It can also act as a bidentate ligand through its two carboxylate groups. Several technetium-99m complexes are used in cholescintigraphy scans (also known as hepatobiliary iminodiacetic acid scans) to evaluate the health and function of the gallbladder.[3][4]

Iminodiacetic acid is an important intermediate in one of the two main industrial processes used to manufacture the herbicide glyphosate. It is used in capillary electrophoresis for modulating peptide mobility. It is also used as a precursor for the manufacture of the indicator xylenol orange.

See alsoEdit


  1. ^ a b Schmitt, Wolfgang; Jordan, Peter A.; Henderson, Richard K.; Moore, Geoffrey R.; Anson, Christopher E.; Powell, Annie K. (2002). "Synthesis, structures and properties of hydrolytic Al(III) aggregates and Fe(III) analogues formed with iminodiacetate-based chelating ligands". Coordination Chemistry Reviews. 228 (2): 115–126. doi:10.1016/S0010-8545(02)00110-8.
  2. ^ Schwarzenbach, G (1952). "Der Chelateffekt". Helv. Chim. Acta. 35 (7): 2344–2359. doi:10.1002/hlca.19520350721.
  3. ^ Michael, Picco. "HIDA scan (cholescintigraphy): Why is it performed?". Mayo Clinic. Retrieved 11 December 2007.
  4. ^ Krishnamurthy, Gerbail T.; Krishnamurthy, Shakuntala (2009). "Imaging Agents". Nuclear Hepatology: A Textbook of Hepatobiliary Diseases. Springer. pp. 54–57. ISBN 978-3-642-00647-0. Retrieved 19 December 2015.