Iminodiacetic acid is the

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula HN(CH₂CO₂H)₂, often abbreviated to IDA. A white solid, the compound is a

dicarboxylic acid In organic chemistry, a dicarboxylic acid is an organic compound containing two carboxyl groups (). The general molecular formula for dicarboxylic acids can be written as , where R can be aliphatic or aromatic.Boy Cornils, Peter Lappe "Dicarbox ...

amine In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

(the nitrogen atom forms a secondary amino group, not an imino group as the name suggests). IDA is a popular

chelating ligand Chelation () is a type of bonding of ions and their molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a Denticity, polydentate (multiple bonded) ligand and a single central metal atom ...

, first introduced in the early 1950s by Schwarzenbach.

Ligand

The iminodiacetate dianion is typically a tridentate

ligand In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's el ...

, forming metal complexes by forming two, fused, five membered

chelate Chelation () is a type of bonding of ions and their molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These l ...

rings. IDA thus forms stronger complexes than the bidentate ligand

glycine Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (G ...

and weaker complexes than the tetradentate ligand

nitrilotriacetic acid Nitrilotriacetic acid (NTA) is the aminopolycarboxylic acid with the formula N(CH2CO2H)3. It is a colourless solid. Its conjugate base nitrilotriacetate is used as a chelating agent for Ca2+, Co2+, Cu2+, and Fe3+. Production and use Nitrilotria ...

. IDA can also act as a bidentate ligand through its two carboxylate groups. Several technetium-99''m'' complexes with bidentate IDA derivatives are used in

cholescintigraphy Cholescintigraphy or hepatobiliary scintigraphy is scintigraphy of the hepatobiliary tract, including the gallbladder and bile ducts. The image produced by this type of medical imaging, called a cholescintigram, is also known by other names depe ...

scans (the so-called "hepatobiliary iminodiacetic acid scans") to evaluate the health and function of the

gallbladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow Organ (anatomy), organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath t ...

. Common IDA derivatives include lidofenin, mebrofenin, and disofenin that replace the secondary amine proton with an amide and aromatic substituent. The proton on the nitrogen atom can be replaced by a carbon atom of a polymer to create an

ion-exchange resin An ion-exchange resin or ion-exchange polymer is a resin or polymer that acts as a medium for ion exchange, that is also known as an ionex. It is an insoluble matrix (or support structure) normally in the form of small (0.25–1.43 mm radiu ...

, such as

chelex 100 Chelex 100 is a chelating material from Bio-Rad used to purify other compounds via ion exchange. It is noteworthy for its ability to bind transition metal ions. It is a styrene-divinylbenzene co-polymer containing iminodiacetic acid groups. A ...

Other applications

Iminodiacetic acid is an important intermediate in one of the two main industrial processes used to manufacture the herbicide

glyphosate Glyphosate (IUPAC name: ''N''-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide and crop desiccant. It is an organophosphorus compound, specifically a phosphonate, which acts by EPSP inhibitor, inhibiting the plant enzyme 5-en ...

. It is used in

capillary electrophoresis Capillary electrophoresis (CE) is a family of electrokinetic separation methods performed in submillimeter diameter capillaries and in micro- and nanofluidic channels. Very often, CE refers to capillary zone electrophoresis (CZE), but other electr ...

for modulating peptide mobility. It is also used as a precursor for the manufacture of the

indicator Indicator may refer to: Biology * Environmental indicator of environmental health (pressures, conditions and responses) * Ecological indicator of ecosystem health (ecological processes) * Health indicator, which is used to describe the health o ...

xylenol orange Xylenol orange is an organic reagent In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used int ...

Synthesis

A most efficient iminodiacetic synthesis dehydrogenates

diethanolamine Diethanolamine, often abbreviated as DEA or DEOA, is an organic compound with the formula HN(CH2CH2OH)2. Pure diethanolamine is a white solid at room temperature, but its tendencies to absorb water and to supercool often results in it being foun ...

over a catalyst.

Related compounds

* N-Methylimidodiacetic acid (MIDA) * N-(2-Carboxyethyl)iminodiacetic acid *

Nitrilotriacetic acid Nitrilotriacetic acid (NTA) is the aminopolycarboxylic acid with the formula N(CH2CO2H)3. It is a colourless solid. Its conjugate base nitrilotriacetate is used as a chelating agent for Ca2+, Co2+, Cu2+, and Fe3+. Production and use Nitrilotria ...

(NTA) * N-hydroxyiminodiacetic acid (HIDA), ( registry number = 87339-38-6) See HIDA scan. *

Thymolphthalexone Thymolphthalexone is a chemical compound from the group of iminodiacetic acid derivatives of thymolphthalein. Its chemical formula is . This is a metallochromic indicator widely used in complexometric titrations, particularly for the determinati ...

References

{{Reflist Dicarboxylic acids Chelating agents Secondary amines