PRODUCTS

NINHYDRIN

Ninhydrin is a widely recognized analytical compound that plays an important role in chemical, biochemical, and forensic applications because of its strong ability to react with free amino groups and generate highly visible colored products.
Ninhydrin is extensively employed for the detection and identification of amino acids, peptides, proteins, and related nitrogen-containing compounds, as well as for the visualization of chromatographic spots and latent fingerprints on porous materials.
Ninhydrin's high sensitivity, reliable color response, and broad compatibility with laboratory techniques make ninhydrin a valuable reagent in analytical chemistry, forensic examination, biochemical research, quality control, and educational laboratory studies.

CAS Number: 485-47-2
EC Number: 207-618-1
Chemical Formula: C9H6O4
Molecular Weight: 178.14 g/mol

Synonyms: NINHYDRIN, 485-47-2, Ninhydrin hydrate, 1,2,3-Indantrione monohydrate, 2,2-Dihydroxy-1H-indene-1,3(2H)-dione, 1H-Indene-1,3(2H)-dione, 2,2-dihydroxy-, Triketohydrindene hydrate, 2,2-Dihydroxy-1,3-indandione, 2,2-Dihydroxy-1,3-indanedione, 1,2,3-Indantrione, 2-hydrate, DTXSID7025716, 1,3-Indandione, 2,2-dihydroxy-, HCL6S9K23A, DTXCID605716, CHEBI:86374, Indantrione Monohydrate, Monohydrate, Indantrione, RefChem:854157, 207-618-1, Ninhydrine, 2,2-Dihydroxyindane-1,3-dione, 2,2-dihydroxyindene-1,3-dione, Ninhydrin Spray, 2,2-dihydroxy-2,3-dihydro-1H-indene-1,3-dione, Trioxohydrindene monohydrate, MFCD00003791, 2,2-Dihydroxy-1,3-dioxoindan, CHEMBL1221925, CCRIS 4849, EINECS 207-618-1, UNII-HCL6S9K23A, BRN 1910963, 2,2-dihydroxy-2-hydrocyclopenta[1,2-a]benzene-1,3-dione, Ningidrin, nin-hydrin, AI3-04464, Ninhydrin, solution, Ninhydrin ACS grade, Ninhydrin solution R1, Ninhydrin solution R2, triketohydrinden hydrate, Ninhydrin, ACS reagent, NINHYDRIN [MI], Ninhydrin, AR, >=99%, SCHEMBL17986, 4-07-00-02786 (Beilstein Handbook Reference), MLS002454421, orb1217988, orb1307170, 3-Indandione, 2,2-dihydroxy-, SCHEMBL29350272, MSK1482, Ninhydrin, >=95.0% (UV), ALBB-033740, HY-D0908, Tox21_200705, 1,2,3-Triketohydrindene Monohydrate, BBL012206, BDBM50324901, Ninhydrin, puriss. p.a., >=99%, SBB009147, STL163548, AKOS004906785, 1H-Indene-1,2,3-trione, 2-hydrate, CS-W018489, EBC-154082, FN06988, NCGC00091114-01, NCGC00091114-02, NCGC00091114-03, NCGC00258259-01, AC-11764, AC-37041, AS-14832, BP-11883, CAS-485-47-2, Ninhydrin, p.a., ACS reagent, 99.0%, PD119090, SMR001372015, ST094931, Ninhydrin spray reagent, 0.2% in ethanol, Ninhydrin, SAJ special grade, >=98.0%, DB-051560, Ninhydrin, ACS reagent, >=98.0% (UV), I0015, N0094, N0719, Ninhydrin, suitable for amino acid detection, NS00022220, EN300-19191, H12009, T19036, AQ-911/40896973, F047866, Q421098, Q-201472, F0001-2517, Ninhydrin, >=98.0%, suitable for amino acid analysis, Z104473086, InChI=1/C9H6O4/c10-7-5-3-1-2-4-6(5)8(11)9(7,12)13/h1-4,12-13

Ninhydrin appears as white to light yellow crystals or powder.
Ninhydrin is a member of the class of indanones that is indane-1,3-dione bearing two additional hydroxy substituents at position 2.

Ninhydrin has a role as a colour indicator and a human metabolite.
Ninhydrin is a member of indanones, a ketone hydrate, a beta-diketone and an aromatic ketone.

Ninhydrin is used in chemical assay for peptide bonds, i.e., protein determinations and has radiosensitizing properties.

Ninhydrin, a tricyclic 1,2,3-trione, is a useful organic building block.
Ninhydrin is an amino acid reagent, which reveals latent fingerprints on porous surfaces like paper, cardboard and raw wood.
Ninhydrin is employed for nitrite detection in various samples, identifying contamination, and is also used as a colorimetric reagent.

Ninhydrin is a highly reliable chemical reagent used to detect the presence of amino acids and free amino groups.
Ninhidrin facilitates visual identification, particularly in techniques such as protein analysis and thin-layer chromatography (TLC), by producing a purplish-blue color.

Ninhydrin is also widely used in forensic laboratories for fingerprint detection.
Ninhydrin's easily soluble structure and high reactivity allow for accurate results.

Ninhydrin can be used as a chromogenic analytical probe for the quantification of amino acids and proteins.

Ninhydrin is an organic compound with the formula C6H4(CO)2C(OH)2.
Ninhydrin is used to detect ammonia and amines.

Upon reaction with these amines, ninhydrin gets converted into deep blue or purple derivatives, which are called Ruhemann's purple.
Ninhydrin is most commonly used to detect fingerprints in forensic cases, as the terminal amines of lysine residues in peptides and proteins sloughed off in fingerprints react with ninhydrin.

Ninhydrin is a white solid that is soluble in ethanol and acetone.
Ninhydrin can be considered as the hydrate of indane-1,2,3-trione.

Ninhydrin is a useful organic building block.
Ninhydrin is an amino acid reagent, which reveals latent fingerprints on porous surfaces like paper, cardboard and raw wood.

Ninhydrin is an organic compound widely used as a sensitive reagent for detecting amino acids, peptides, and other compounds containing free amino groups.
Ninhydrin reacts with primary amino groups to produce an intense purple-blue color known as Ruhemann’s purple, making it especially valuable in analytical chemistry, biochemistry, chromatography, and forensic science.
Ninhydrin is commonly used for visualizing amino acids on chromatographic media and developing latent fingerprints on porous surfaces.

Ninhydrin is a versatile chemical compound widely recognized for its applications in analytical chemistry and biochemistry.
Ninhydrin is primarily used for the detection of amino acids and proteins through colorimetric reactions.

When ninhydrin reacts with amino acids, Ninhydrin produces a deep blue or purple color, making it an invaluable tool in various laboratory settings, including forensic science for fingerprint analysis and in the study of protein structures.
Ninhydrin's sensitivity and specificity allow researchers to identify and quantify amino acids in complex mixtures, enhancing its utility in both academic and industrial laboratories.

In addition to its role in amino acid detection, ninhydrin is also employed in the synthesis of various organic compounds and as a reagent in chromatography.
Ninhydrin's unique ability to form stable complexes with amino acids makes it a preferred choice for researchers looking to streamline their analytical processes.
With its proven track record and broad applicability, ninhydrin stands out as a crucial reagent for professionals in the fields of chemistry, biology, and forensic science.

Ninhydrin, a tricyclic 1,2,3-trione is a useful organic building block.
Ninhydrin is an amino acid reagent, which reveals latent fingerprints on porous surfaces like paper, cardboard and raw wood.
Ninhydrin is employed for nitrite detection in various samples, identifying contamination, and is also used as a colorimetric reagent.

Ninhydrin is used for the determination of amino groups in amino acids, peptides and proteins.
Ninhydrin finds application in forensic science for the analysis of latent fingerprints on porous surfaces such as paper.

Ninhydrin is also used in thin layer chromatography (TLC) to monitor the progress of chemical reactions.
In Kaiser test, Ninhydrin plays an important role to monitor the deprotection in solid phase peptide synthesis.

Ninhydrin is defined as a standard technique for detecting free amines, used both as a qualitative method to evaluate amide coupling reactions on solid support and as a useful stain for monitoring reactions involving amines in solution.

Uses of Ninhydrin:
Ninhydrin is used as a laboratory reagent to detect amino and carboxyl groups in peptides and proteins.
Ninhydrin can be used in Kaiser test to monitor deprotection in solid phase peptide synthesis.
The chain is linked via its C-terminus to the solid support, with the N-terminus extending off it.

When that nitrogen is deprotected, a ninhydrin test yields blue.
Amino-acid residues are attached with their N-terminus protected, so if the next residue has been successfully coupled onto the chain, the test gives a colorless or yellow result.

Ninhydrin is also used in qualitative analysis of proteins.
Most of the amino acids, except proline, are hydrolyzed and react with ninhydrin.

Also, certain amino acid chains are degraded.
Therefore, separate analysis is required for identifying such amino acids that either react differently or do not react with ninhydrin at all.

The rest of the amino acids are then quantified colorimetrically after separation by chromatography.
Oftentimes specialized amino acid analyzers using HPLC technology and post-column derivatization with ninhydrin are applied for the detection of free and protein-bound amino acids, as required throughout the EU in the feed industry.

A solution suspected of containing the ammonium ion can be tested by ninhydrin by dotting it onto a solid support (such as silica gel); treatment with ninhydrin should result in a dramatic purple color if the solution contains this species.
In the analysis of a chemical reaction by thin layer chromatography (TLC), the reagent can also be used (usually 0.2% solution in either n-butanol or in ethanol).
Ninhydrin will detect, on the TLC plate, virtually all amines, carbamates and also, after vigorous heating, amides.

Upon reaction with ninhydrin, amino acids undergo decarboxylation.
The released CO2 originates from the carboxyl carbon of the amino acid.

This reaction has been used to release the carboxyl carbons of bone collagen from ancient bones for stable isotope analysis in order to help reconstruct the palaeodiet of cave bears.
Release of the carboxyl carbon (via ninhydrin) from amino acids recovered from soil that has been treated with a labeled substrate demonstrates assimilation of that substrate into microbial protein.
This approach was successfully used to reveal that some ammonium oxidizing bacteria, also called nitrifying bacteria use urea as a carbon source in soil.

Forensics:
A ninhydrin solution is commonly used by forensic investigators in the analysis of latent fingerprints on porous surfaces such as paper.
The amino acids present in the minute sweat secretions that gather on the finger's unique ridges transfer to surfaces that are touched.

Exposure of the surface to ninhydrin converts the amino acids into visibly colored products and thus reveals the print.
The test solutions suffer from poor long-term stability, especially if not kept cold.

To further enhance the ability of ninhydrin, a solution of 1,2-indandione and zinc chloride (IND-Zn) can be used prior to ninhydrin.
This sequence leads to greater overall reaction of the amino acids, possibly by IND-Zn helping to release them from the surface for the subsequent ninhydrin reaction.

Applications of Ninhydrin:
Ninhydrin is used for the determination of amino groups in amino acids, peptides and proteins.
Ninhydrin finds application in forensic science for the analysis of latent fingerprints on porous surfaces such as paper.

Ninhydrin may be used as a reagent for the quantification of amino acids and peptides by photometric method and colorimetric method.
Ninhydrin may be used to prepare the ninhydrin reagent, by mixing ninhydrin and hydrindantin (reduced form of ninhydrin) in dimethyl sulfoxide.

Ninhydrin is used in manual ninhydrin method for the quantitative determination of amino acids.
Ninhydrin is used in the detection and assay of peptides, amino acids, amines, and amino sugars yielding highly fluorescent ternary compounds with aldehydes and primary amines.

Reaction with sarcosine or proline gives azomethine ylides.
Ninhydrin is used for the detection of free amino groups in amino acids, peptides and proteins.

Ninhydrin is used in the detection and assay of peptides, amino acids, amines, and amino sugars yielding highly fluorescent ternary compounds with aldehydes and primary amines.
Reaction with sarcosine or proline gives azomethine ylides.

Reactivity of Ninhydrin:
Ninhydrin exists in equilibrium with the triketone indane-1,2,3-trione, which reacts readily with nucleophiles (including water).
Whereas for most carbonyl compounds, a carbonyl form is more stable than a product of water addition (hydrate), ninhydrin forms a stable hydrate of the central carbon because of the destabilizing effect of the adjacent carbonyl groups.

To generate the ninhydrin chromophore [2-(1,3-dioxoindan-2-yl)iminoindane-1,3-dione], the amine must condense to give a Schiff base.
The reaction of ninhydrin with secondary amines gives an iminium salt, which is also coloured, generally being yellow–orange.

History of Ninhydrin:
Ninhydrin was discovered in 1910 by the German-English chemist Siegfried Ruhemann (1859–1943).
In the same year, Ruhemann observed ninhydrin's reaction with amino acids.
In 1954, Swedish investigators Oden and von Hofsten proposed that ninhydrin could be used to develop latent fingerprints.

Stability and Reactivity of Ninhydrin:

Chemical stability:
Stable under normal storage and handling conditions.

Conditions to avoid:
Avoid excessive heat, moisture, and prolonged exposure to incompatible materials.

Incompatible materials:
Strong oxidizing agents, strong acids, and strong bases.

Hazardous decomposition products:
Thermal decomposition may produce carbon oxides and nitrogen-containing fumes.

Handling and Storage of Ninhydrin:

Safe handling:
Avoid dust formation and direct contact with skin and eyes.
Use adequate ventilation.

Storage conditions:
Store tightly closed in a cool, dry, well-ventilated place.

First Aid Measures of Ninhydrin:

Inhalation:
Move to fresh air and seek medical attention if symptoms persist.

Skin contact:
Wash thoroughly with soap and water.

Eye contact:
Rinse cautiously with water for several minutes.

Ingestion:
Rinse mouth and seek medical advice if discomfort occurs.

Firefighting Measures of Ninhydrin:

Suitable extinguishing media:
Use water spray, foam, dry chemical, or CO₂.

Protective equipment:
Firefighters should wear suitable protective equipment.

Accidental Release Measures of Ninhydrin:

Personal precautions:
Avoid dust formation and ensure adequate ventilation.

Cleanup methods:
Collect spilled material carefully into a suitable closed container.

Exposure Controls / Personal Protective Equipment of Ninhydrin:

Engineering controls:
Provide adequate general or local ventilation.

Personal protection:
Wear protective gloves, safety glasses, and suitable protective clothing.
Use respiratory protection if significant dust is generated.

Identifiers of Ninhydrin:
Grade: ACS reagent
Quality Level: 200
Description: identification and melting point passes test
Form: solid
Color: white to brownish white, crystals
Melting Point: 250 °C (dec.) (lit.)
Solubility: H2O: passes test
Suitability: passes test for sensitivity to amino acids
SMILES String: OC1(O)C(=O)c2ccccc2C1=O
InChI: 1S/C9H6O4/c10-7-5-3-1-2-4-6(5)8(11)9(7,12)13/h1-4,12-13H
InChI Key: FEMOMIGRRWSMCU-UHFFFAOYSA-N

Synonym(s): 1,2,3-Indantrione monohydrate, 2,2-Dihydroxy-1,3-indanedione, Trioxohydrindene monohydrate
Empirical Formula (Hill Notation): C9H6O4
CAS Number: 485-47-2
Molecular Weight: 178.14
Beilstein: 1910963
EC Number: 207-618-1
MDL Number: MFCD00003791
PubChem Substance ID: 24849098
NACRES: NA.21

CAS Number: 485-47-2
3D Model (JSmol): Interactive image
ChEMBL: ChEMBL1221925
ChemSpider: 9819
ECHA InfoCard: 100.006.926
EC Number: 213-340-1
PubChem CID: 10236
UNII: HCL6S9K23A
CompTox Dashboard (EPA): DTXSID7025716
InChI: InChI=1S/C9H6O4/c10-7-5-3-1-2-4-6(5)8(11)9(7,12)13/h1-4,12-13H
Key: FEMOMIGRRWSMCU-UHFFFAOYSA-N
InChI: InChI=1/C9H6O4/c10-7-5-3-1-2-4-6(5)8(11)9(7,12)13/h1-4,12-13H
Key: FEMOMIGRRWSMCU-UHFFFAOYAM
SMILES: O=C2c1ccccc1C(=O)C2(O)O

Empirical Formula (Hill Notation): C9H6O4
CAS Number: 485-47-2
Molecular Weight: 178.14
NACRES: NA.21
PubChem Substance ID: 24849098
UNSPSC Code: 12352100
EC Number: 207-618-1
MDL Number: MFCD00003791
Beilstein/REAXYS Number: 1910963
Form: solid

Properties of Ninhydrin:
Chemical Formula: C9H6O4
Molar Mass: 178.143 g·mol−1
Appearance: White solid
Density: 0.862 g/cm3
Melting Point: 250 °C (482 °F; 523 K) (decomposes)
Solubility in Water: 20 g L−1

Product Name: Ninhydrin, ACS reagent
Grade: ACS reagent
Quality Segment: 200
Description: identification and melting point passes test
Form: solid
Color: white to brownish white, crystals
Melting Point: 250 °C (dec.) (lit.)
Solubility: H2O: passes test
Suitability: passes test for sensitivity to amino acids
Functional Group: hydroxyl, ketone
SMILES String: OC1(O)C(=O)c2ccccc2C1=O
InChI: 1S/C9H6O4/c10-7-5-3-1-2-4-6(5)8(11)9(7,12)13/h1-4,12-13H
InChI Key: FEMOMIGRRWSMCU-UHFFFAOYSA-N

Molecular Weight: 178.14 g/mol
XLogP3-AA: 0.1
Hydrogen Bond Donor Count: 2
Hydrogen Bond Acceptor Count: 4
Rotatable Bond Count: 0
Exact Mass: 178.02660867 Da
Monoisotopic Mass: 178.02660867 Da
Topological Polar Surface Area: 74.6 Å²
Heavy Atom Count: 13
Formal Charge: 0
Complexity: 243
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: 1
Compound Is Canonicalized: Yes

Specifications of Ninhydrin:
Form: Crystals or powder or crystalline powder
Water Content (Karl Fischer Titration): 7.5-11.6% (0.8-1.3 waters)
Appearance (Color): White to cream or pale yellow
Identification (FTIR): Conforms
Assay (HPLC): ≥98.5%

Names of Ninhydrin:

Preferred IUPAC name:
2,2-Dihydroxy-1H-indene-1,3(2H)-dione

Other names:
2,2-Dihydroxyindane-1,3-dione
1,2,3-Indantrione hydrate