TRIAMMONIUM CITRATE

Molecular Formula: C6H17N3O7
Molecular Weight: 243.22
CAS: 3458-72-8
European Community (EC) Number: 222-394-5
MDL number: MFCD00036406

Triammonium citrate is a citrate salt in which all three carboxy groups are deprotonated and associated with ammonium ions as counter-cations.
Ammonium citrate tribasic has a role as a food emulsifier and a buffer.
Triammonium citrate is an ammonium salt and a citrate salt.

White solid; [JECFA] White crystalline powder; [Alfa Aesar MSDS]

Ammonium citrate is a white granular solid.
Triammonium citrate is soluble in water.
The primary hazard is the threat to the environment.
Immediate steps should be taken to limit its spread to the environment.
Ammonium citrate tribasic is used in pharmaceuticals, and in chemical analysis.
White to off-white crystals or powder

Citric acid triammonium salt is registered under the REACH Regulation and is manufactured in and / or imported to the European Economic Area, at ≥ 10 to < 100 tonnes per annum.
Ammonium citrate is used by professional workers (widespread uses), in formulation or re-packing, at industrial sites and in manufacturing.

A wide quality array of products comprising Chemical Compound, Organic Compound, Boric Acid, Carnauba Wax, Crude Iodine, Ammonium Ferric Citrate, Gelatinous Substance, Inorganic Compound, Immersion Oil, Laboratory Chemicals,Magnesium Metal Turning, Wool Wax, Acenaphthene Chemical, Magnesium Metal Powder and Malt Sugar.

Triammonium citrate is a white powder with a slight ammonia odor and belongs to the group of organic salts.
This salt is a very weak alkaline compound.
Triammonium citrate has many applications in industry, one of which is Ammonium citrates use as a chelating agent in metal cations such as iron, which increases their solubility and biological properties in compounds.

Chemical Role(s):
Food Emulsifier
A food additive used to form or maintain a uniform emulsion of two (or more) phases in a food.

Buffer
Any substance or mixture of substances that, in solution (typically aqueous), resists change in pH upon addition of small amounts of acid or base.

Biological Role(s):
Food Emulsifier
A food additive used to form or maintain a uniform emulsion of two (or more) phases in a food.

Triammonium citrate is a chemical compound patented prior to 1986.
In the European Union, Ammonium citrate is known as food additive number E380 and in the United States Ammonium citrate is designated as an indirect food additive used only as a component of adhesives and as a substance directly added to human food.
Triammonium citrate is the ammonium salt of citric acid (E330).
Triammonium citrate is therefore a natural acid present in most fruits.
Ammonium citrate tribasic is produced industrially by a fungus (Aspergillus niger) grown on a sweet nutrient solution.
The role of triammonium citrate is to regulate the acidity of certain non-alcoholic soft drinks.
Triammonium citrates antioxidant capacity also enables Ammonium citrate to prevent the browning of foodstuffs.
Triammonium citrate has also been used to clean paints since the mid-1980s because of Ammonium citrates effectiveness in removing the coating.

Ammonium citrate - the ammonium salt of citric acid.
Ammonium citrate consists of three ammonium ions (NH4) + and the citrate (C6H5O7)3-, forming colorless crystals which dissolve well in water.

QSAR prediction of toxicity to aquatic algae and cyanobacteria using ECOSAR v1.11, result EC50 = 19868.549 mg/L at 25°C for Triammonium citrate.
There is no data available regarding the toxicity to algar and cyanobacteria for Triammonium citrate.
Published results are available for the constituents of Triammonium citrate, namely citric acid and ammonium ions.
Determination growth rate inhibition by ammonia was conducted with Chlorella vulgaris, measurement of growth rate via determination of chlorophyll content during a 18 days period.
EC50 = 2700 mg (NH4)2SO4/L or 1000 mg N x L-1.
For citric acid the toxicity threshold was determined, Scenedesmus quadricauda were incubated with up to 14 concentrations of the test item with a spacing factor of 2, the toxicity threshold was determined at 640 mg/L.

Acidity Regulator / Buffering Agent - Changes or maintains the acidity or basicity of food/cosmetics.
Triammonium citrate is the ammonium salt of citric acid.
As a food additive (E number 380), Ammonium citrate is used as acidity regulator, buffer and emulsifier.
Citric acid triammonium salt can be found in chocolate confectionery and cheese spreads.
Citric acid triammonium salt is approved to use as food additive in EU.

Ammonium citrate belongs to the class of organic compounds known as tricarboxylic acids and derivatives.
These are carboxylic acids containing exactly three carboxyl groups.
Ammonium citrate is an extremely weak basic (essentially neutral) compound (based on its pKa).

Citric acid triammonium salt is known in the European E number food additive series as E380.
Triammonium citrate is known in the United States as "an indirect food additive for use only as a component of adhesives", and as a "substance added directly to human food affirmed as generally recognized as safe (GRAS)."

Uses of Ammonium citrate
Pharmaceuticals; rustproofing; cotton printing; plasticizer, analytical reagent in determination of phosphate in fertilizer.
Ammonium citrate has been used as a source of non-protein nitrogen in chicken food supplements.
Buffering agent; chelating agent

Consumer Uses
ECHA has no public registered data indicating whether or in which chemical products the substance might be used.
ECHA has no public registered data on the routes by which Ammonium citrate is most likely to be released to the environment.

Uses at industrial sites
Ammonium citrate is used in the following products: pH regulators and water treatment products, metal surface treatment products, metal working fluids and laboratory chemicals.
Citric acid triammonium salt is used in the following areas: health services and scientific research and development.
Ammonium citrate is used for the manufacture of: chemicals, food products and metals.
Release to the environment of Ammonium citrate can occur from industrial use: in processing aids at industrial sites, in the production of articles, as an intermediate step in further manufacturing of another substance (use of intermediates) and as processing aid.

Widespread uses by professional workers
Citric acid triammonium salt is used in the following products: pH regulators and water treatment products, laboratory chemicals, perfumes and fragrances, pharmaceuticals and cosmetics and personal care products.
Ammonium citrate is used in the following areas: scientific research and development and health services.
Ammonium citrate is used for the manufacture of: chemicals and food products.
Other release to the environment of Ammonium citrate is likely to occur from: indoor use (e.g. machine wash liquids/detergents, automotive care products, paints and coating or adhesives, fragrances and air fresheners).

Triammonium citrate is a food additive and as such may be used in the following foods under the conditions of good manufacturing practices (GMP) as outlined in the Preamble of the Codex GSFA.
Although not listed below, Triammonium citrate could also be used in heat-treated butter milk of food category 01.1.1 and spices of food category 12.2.1.
Note that food categories listed in the Annex to Table 3 were excluded accordingly.
Triammonium citrate is acceptable in foods conforming to the following commodity standards: CS 57-1981, CS 13-1981.
Triammonium citrate is a: Acidity regulator

Ammonium citrate is a white, granular, water-soluble salt of ammonia and citric acid.
Triammonium citrate is used in a neutral solution for determining the phosphorus content of phosphate fertilizers (such as calcium hydrogen phosphate (CaHPO4)), that are insoluble in water but dissolve in complexing citrate solutions.
The fertilizer residue, after extraction of watersoluble phosphorus, is re-extracted with a neutral or strongly alkaline solution of 1 normal (1N) ammonium citrate for a prescribed period, and the slurry filtered.
Citrate-soluble phosphorus is the phosphorus content in the filtrate and is expressed as a percentage by weight of the fertilizer.
The extraction of phosphate with 1N ammonium citrate is carried out routinely for 30 minutes, first at room temperature and then at 4O℃ For neutral ammonium citrate solution, a temperature of 65℃ is preferred.
Some European countries use an alkaline ammonium citrate solution, which extracts smaller amounts of phosphorus.
Some experts consider it to be better correlated with phosphorus uptake and plant growth.
However, most countries use a neutral normal ammonium citrate solution for extracting citrate soluble phosphorus.

Ammonium citrate tribasic is widely utilized as a buffering agent and emulsifier in food industry.
Triammonium citrate acts as a complexing agent in electroplating industry and is also used for metal surface cleaning.
Ammonium citrate is employed in chemical analysis and in water treatment.
Triammonium citrate serves as a chemical reagent in analytical chemistry to determine the efficient phosphate levels in phosphate salts and fertilizer.
Ammonium citrate is used in industries for water treatment, as a ceramic dispersant, a detergent material and a component for soil improvement.
Ammonium citrate tribasic is used in medical and electronics industries as an auxiliary infiltration agent.

Crystallization grade Ammonium citrate tribasic for formulating screens or for optimization.

Triammonium citrate is the ammonium salt of citric acid (E330).
The latter is a natural acid present in most fruits.
On an industrial scale, it is produced by a fungus (Aspergillus niger) cultured on a sugary nutrient solution.
Triammonium citrate is an acidity regulator commonly used in non-alcoholic soft drinks such as sodas.
Ammonium citrate tribasic also prevents food from browning and enhances the action of other antioxidants.

Triammonium Citrate as a Food Additive:
Triammonium citrate is mainly used as a food additive, usually for flavor or preservative.
Ammonium citrate is used as a flavoring agent in certain types of water and carbonated beverages.
Ammonium citrate tribasic is added to solutions as a weak acid conjugate base as well as a buffering agent to regulate acidity and resistance to pH changes.
Citric acid triammonium salt is also used to control acidity in gelatinous desserts. Like citric acid

Triammonium Citrate in Cosmetics:
This combination is used in all types of cosmetics, baby products, bath products, soaps and detergents, hair dyes, and hair and skin care products.
Cosmetic manufacturers use this combination to adjust the pH of their desired formulation so as not to irritate the skin.

Use Classification
-Food additives
-Food Additives -> ACIDITY_REGULATOR; -> JECFA Functional Classes
-Cosmetics -> Buffering; Chelating

Chemical and Physical Properties

Property Name and Property Value
Molecular Weight: 243.22
Hydrogen Bond Donor Count: 4
Hydrogen Bond Acceptor Count: 7
Rotatable Bond Count: 2
Exact Mass: 243.10664989
Monoisotopic Mass: 243.10664989
Topological Polar Surface Area: 144 Ų
Heavy Atom Count: 16
Formal Charge: 0
Complexity: 211
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 4
Compound Is Canonicalized: Yes
Density: 1.48
Assay: ≥97% (titration)
Bp: 100 °C (lit.)
Mp: 185 °C (dec.) (lit.)
Density: 1 g/mL at 25 °C (lit.)
Melting pointca: 180° dec.

Appearance: White crystalline powder (est)
Food Chemicals Codex Listed: No
Boiling Point: 309.60 °C. @ 760.00 mm Hg (est)
Vapor Pressure: 0.000057 mmHg @ 25.00 °C. (est)
Flash Point: 311.00 °F. TCC ( 155.20 °C. ) (est)
logP (o/w): -1.721 (est)

Experimental Melting Points:
180 °C (Decomposes) Alfa Aesar A16973
185 °C LabNetwork (old) LN00193873
185 °C SynQuest 4133-1-03
185 °C (Decomposes) Sigma-Aldrich SIGMA-A1332
185 °C (Decomposes) Oakwood 099397

Experimental Boiling Point: 100 °C Sigma-Aldrich SIGMA-A1332
Experimental LogP: -2.247 LabNetwork (old) LN00193873
Experimental Density: 1 g/mL Sigma-Aldrich SIGMA-A1332
Appearance (Solution): Clear with a very light yellow to brown tint color

HR2-759 titrated to pH 7.0 using HCl (used in SaltRx, Index, PEG/Ion, PegRx, and PEG/Ion 400)
Measured Conductivity Range: 95.4 - 97.9 mS/cm at 25°C
Measured Refractive Index Range: 1.43139 - 1.43241 at 20°C

HR2-865 is not titrated to a specific pH (used in GRAS Screen 1, 2, 3, 4, 7, and PEG/Ion 400)
Measured pH Range:  7.7 at 25°C
Measured Conductivity Range:  95.8 - 96.2 mS/cm at 25°C
Measured Refractive Index Range:   1.43204 - 1.43232 at 20°C

Application(s)
diagnostic assay manufacturing
A 2105 (OTTO) tri-Ammonium citrate, 98% Cas 3458-72-8 - used in pharmaceuticals, rust proofing, cotton printing and plasticizers.

Names and Identifiers
Computed Descriptors

InChI: 1S/C6H8O7.3H3N/c7-3(8)1-6(13,5(11)12)2-4(9)10;;;/h13H,1-2H2,(H,7,8)(H,9,10)(H,11,12);3*1H3
InChI Key: YWYZEGXAUVWDED-UHFFFAOYSA-N
Canonical SMILES: C(C(=O)[O-])C(CC(=O)[O-])(C(=O)[O-])O.[NH4+].[NH4+].[NH4+]
Molecular Formula: C6H17N3O7
IUPAC Name: triazanium;2-hydroxypropane-1,2,3-tricarboxylate

Other Identifiers

UN Number: 3077
UNII: J90A52459R
DSSTox Substance ID: DTXSID5020079
NACRES: NA.25
Beilstein: 3779194
MDL number: MFCD00036406

Color/Form
-Granules or crystals
-Colorless crystals
-White granules

Odor
-Slight ammoniacal

Solubility
-Freely soluble in water
-Slightly soluble in alcohol
-Soluble in about 1 part water

Density
-1.48 at 68 °F (USCG, 1999)
-1.48 g/cu cm

pH
-pH = 4.3 (0.1 molar soln in water)

FEATURES
Sterile filtered solution
Formulated in Type 1+ ultrapure water: 18.2 megaohm-cm resistivity at 25°C, < 5 ppb Total Organic Carbon, bacteria free (<1 Bacteria (CFU/ml)), pyrogen free (<0.03 Endotoxin (EU/ml)), RNase-free (< 0.01 ng/mL) and DNase-free (< 4 pg/µL)

Methods of Manufacturing
-Made by neutralization of citric acid with ammonia.
-EPA TSCA Commercial Activity Status
1,2,3-Propanetricarboxylic acid, 2-hydroxy-, ammonium salt (1:3): ACTIVE
-Component of algicidal compound.
-Reported product category: shampoos (non-coloring)

The main raw material of Triammonium Citrate is Citric Acid.
Citric Acid is available in two forms i.e. Anhydrous & Monohydrate.
Citric Acid is produced by fermentation process in which a carbohydrate source is utilized such as corn based starch and sugar beet molasses.
Fermentation yields a crude purity product which requires further refining.
One refining technique utilities a precipitation process, this process first uses lime to produce calcium citrate solids, this is then treated with sulphuric acid which produces a partially purified soluble citric acid and calcium sulphate as a by-product.
Another technique used is solvent extraction.
These processes produce streams which require demineralization by ion exchange.
Triammonium Citrate is prepared by treating Citric acid with Ammonium Bicarbonate.

Formulations/Preparations
-Grades or Purity: Reagent
-Diammonium citrate is marketed as granules or crystals.

Stability and Reactivity

Air and Water Reactions
Water soluble.

Reactive Group
Salts, Acidic

Ammonium citrate is an indirect food additive for use only as a component of adhesives.
Ammonium citrate added directly to human food affirmed as generally recognized as safe (GRAS).

Reactivity Profile
Acidic salts, such as AMMONIUM CITRATE, are generally soluble in water.
The resulting solutions contain moderate concentrations of hydrogen ions and have pH's of less than 7.0. They react as acids to neutralize bases.
These neutralizations generate heat, but less or far less than is generated by neutralization of inorganic acids, inorganic oxoacids, and carboxylic acid.
They usually do not react as either oxidizing agents or reducing agents but such behavior is not impossible.
Many of these compounds catalyze organic reactions.

Classification
MeSH Tree
MeSH Tree > Chemicals and Drugs Category > Organic Chemicals > Amines > Quaternary Ammonium Compounds > Supplementary Records > ammonium citrate

ChEBI Ontology 
ChEBI Ontology > chemical entity > molecular entity > main group molecular entity > p-block molecular entity > pnictogen molecular entity > nitrogen molecular entity > ammonium compound > ammonium salt > triammonium citrate

Formulation or re-packing
Ammonium citrate is used in the following products: pH regulators and water treatment products, laboratory chemicals, perfumes and fragrances, pharmaceuticals and cosmetics and personal care products.
Release to the environment of Ammonium citratea can occur from industrial use: formulation of mixtures and formulation in materials.

Laboratories for the analysis of Triammonium Citrate:
At Analytice, we are able to offer you the analysis and dosage of triammonium citrate in various matrices through our network of ISO 17 025 accredited laboratories recognized by the Cofrac (ILAC full member) for analysis in the work environment.

Example of triammonium citrate determination:
Sampling medium: Specific PVC filter (Na/K/Cr6)
Analytical Technique: Ion Chromatography
Method: OSHA ID-188
LQ: 7 µg NH3/Support
 
Specifications
 
Appearance (Colour): A white
Appearance (Form): Deliquescent powder
Solubility (Turbidity) 10% aq. solution: Clear
Solubility (Colour) 10% aq. solution: Colourless
Assay: min. 98.5%
pH (5% aq. solution): 6.0 - 7.5
Chloride (CI): max. 0.001%
Sulphate (SO4): max. 0.005%
Iron (Fe): max. 0.0005%
Heavy Metals (Pb): max. 0.0005%
Oxalate (C2O4): max. 0.01%
Copper (Cu): max. 0.0001%
Potassium (K): max. 0.003%
Sodium (Na): max. 0.004%
Readily carbonisable substances: Passes test
Reducing Substances: Passes test

Property and Value
logP: -1.3
pKa (Strongest Acidic): 3.05    
pKa (Strongest Basic): -4.2
Physiological Charge: 3
Hydrogen Acceptor Count: 7
Hydrogen Donor Count: 4
Polar Surface Area: 132.13 Ų
Rotatable Bond Count: 5
Refractivity: 35.62 m³·mol⁻¹
Polarizability: 15.51 ų
Number of Rings: 0
Bioavailability: Yes
Rule of Five: Yes
Ghose Filter: No
Veber's Rule: No
MDDR-like Rule: No

Additional information
Triammonium citrate is the ammonia salt of citric acid in which all carboxy groups are deprotonated and associated with ammonium ions as counter-cations.
Citric acid-triammonium salts physical appearance are white crystals at 1013 Pa and ambient temperature.
Furthermore, Triammonium citrate is very water soluble (>1000 mg/L, Merck Index, 2001).
Triammonium citrate is used as food additive mainly due to its buffer capacity, an acceptable daily intake (ADI) was not derived, the daily intake was not limited (JEFCA report, 1979), thus Ammonium citrate is expected to be of low acute toxicity.
Once, dissolved in water the ions will dissociate thereby generating free citric acid and ammonium ions.
Both molecules are ubiquitously present and also integral parts of the eukaryotic intermediary metabolism.
Based on this reaction behavior Ammonium citrate can be assumed that during testing of toxicity to aquatic invertebrates, algae and cyanobacteria, these organisms are mainly exposed to the free ions, namely ammonium-ions and citrate.
Triammonium citrate is well known that citric acid due to Ammonium citrates pivotal role in intermediary metabolism has a low toxicity.
The acute oral toxicity was evaluated in several rodent and non-rodent species revealing LD50 values between 3000 mg/kg bw and 5500 mg/kg bw and a LDLo of 7000 mg/kg bw in rabbits, respectively[1][2][3].
Low toxicity was also reported for aquatic species like Carcinus maenas, 48h LC50 = 160 mg/L[4].
Nelson & Kursar determined the median 24h LD50 for brine shrimp to be 226.7 mg/L[5].
In the green alga Scenedesmus quadricauda the toxicity threshold was determined to be 640 mg/L which corresponds to an estimated NOEC of 427 mg/L[6].
However, possible adverse effects may result from the irritation potential of citric acid based on changes in pH.
However, the simultaneous presence of ammonium ions in the substance of interest will prevent changes in pH, thus, no toxicity up to the limit concentration is expected.
Additionally, in an OECD assessment report test results from several aquatictoxicity test with citric acid in several aquatic species were summarized (OECD SIDS Initial Assessment Report for 11th SIAM, 2001).
In none of the tests citric acid exhibit a LC50 or EC50 value beneath the limit concentration although there were EC0 values reported for Daphnia magna of 73 and 85 mg/L, respectively.
A considerable change in pH in these tests cannot be excluded, hence these effect values are assumed to be related to an increased acidity.
Similar information are available for ammonium.
The ionized form of ammonia is well tolerated in green algae for ammonium assimilation and subsequent metabolism (Turpin et a.., 1990[7];[8][9]).
In an OECD report (SIDS Initial Assessment Report For SIAM 19, 2004) for Ammonium sulphate it was described that the ration of unionized ammonia to ionized ammonium is increasing in some of the conducted tests, thus, leading to signs of toxicity.
NH4+and NH3coexist in aqueous solution in adynamic pH-dependent equilibrium.
Under basic conditions (pH >10), ammonia (NH3) redominates whereas the ammoniumion (NH4+) is the dominant species in weakly basic to neutral (environmental) conditions.
With decreasing pH, the ammonium cation becomes the only species.
This increasing ratio is known to be correlated with pH- and temperature changes.
Since the substance of interest exhibits a buffer capacity due to the contained citric acid it can be assumed that an increased generation of unionized ammonia is negligible for the substance of interest.
However, again neither in Daphnia magna nor in green freshwater algae the LC/EC50 values were below the limit concentration, thus, low toxicity is expected.
These results are in line with the results of QSAR predictions that were performed with either Triammonium citrate or citric acid.
Although the results are afflicted with a high uncertainty based on the ionic structure which is not applicable with the simple non-polar narcosis model used and therefore possibly underestimates the toxicity, due to the aforementioned test results with the constituents of the salt underpin the determined values.
Due to the stoichiometric distribution of ammonium in Triammonium citrate, the low toxicity of citric acid and the sensitive balance between ammonia and ammonium depending on the pH, the ammonium ion is considered to be the toxicity-determining component and the EC50 for ammonium sulfate is used as the value for the chemical safety assessment
Taken together, both constituents (ions) of the substance exhibit a low toxicity and based on the ionic structure and its dissociation into free ions, aquatic organisms are expected to be exposed only to these ions and thus, the substance itself is also considered to be of very low toxicity and does not need to be classified as hazardous.

Synonyms

3458-72-8
Triammonium citrate
Ammonium citrate tribasic
Ammonium citrate
Ammonium citrate (3:1)
1,2,3-Propanetricarboxylic acid, 2-hydroxy-, triammonium salt
Citric acid triammonium salt
UNII-J90A52459R
Citrate (Triammonium)
2-Hydroxy-1,2,3-propanetricarboxylic acid triammonium salt
triazanium;2-hydroxypropane-1,2,3-tricarboxylate
J90A52459R
triammonium 2-hydroxypropane-1,2,3-tricarboxylate
tri(azaniumyl) 2-hydroxypropane-1,2,3-tricarboxylate
2-hydroxy-1,2,3-propanetricarboxylic acid, ammonium salt (1:3)
EINECS 222-394-5
3012-65-5
CHEBI:63037
AMMONIUM CITRATE, TRIBASIC
DTXSID10889469
1,2,3-Propanetricarboxylic acid, 2-hydroxy-, ammonium salt (1:3)
AKOS009158559
DB-048656
ammonium 2-hydroxypropane-1,2,3-tricarboxylate
UNII-3B4TDL7WDP component YWYZEGXAUVWDED-UHFFFAOYSA-N