Chlorazol Black

Chlorazole Black E, 4-Amino-3-[[4′-[(2,4-diaminophenyl)azo][1,1′-biphenyl]-4-yl]azo]-5-hydroxy-6-(phenylazo)-2,7-naphthalenedisulfonic acid disodium salt, Direct Black 38
Empirical Formula (Hill Notation):
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Quality Level


Dye content, ≥45% (based on Nitrogen)


hematology: suitable
histology: suitable


H2O: 1 mg/mL

Featured Industry

Diagnostic Assay Manufacturing

storage temp.

room temp

SMILES string




InChI key


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General description

Chlorazol Black has strong affinity for cellulose and chitin. In plant tissues, it helps to differentiate between cellulose and lignin. It also helps in distinguishing fungal bodies from artefacts due to chitin staining. It is also used as an auxiliary stain for chromosomes.


Chlorazol Black has been used to monitor the infection of mycorrhizal Allium porrum in plant roots. It has also been used for the staining of copepods.


5, 25 g in glass bottle


Exclamation markHealth hazard

Signal Word


Hazard Statements

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis
Certificate of Origin
Jianyong An et al.
The New phytologist, 224(1), 396-408 (2019-05-31)
Plants form a mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, which facilitates the acquisition of scarce minerals from the soil. In return, the host plants provide sugars and lipids to its fungal partner. However, the mechanism by which the AM...
Mutagenic activation of the benzidine-based dye direct black 38 by human intestinal microflora.
C E Cerniglia et al.
Mutation research, 175(1), 11-16 (1986-09-01)
R P Bos et al.
Toxicology, 40(2), 207-213 (1986-08-01)
The role of the rat intestinal flora in the azo reduction of some benzidine-based dyes was studied in vitro and in vivo. The formation of benzidine was measured after anaerobic incubation of direct black 38, direct blue 6 and direct...
Mercedes Conradi et al.
ZooKeys, (791), 71-95 (2018-11-06)
Spaniomolgus is a symbiotic genus of copepods of the poecilostomatoid family Rhynchomolgidae and is known to be associated with shallow-water reef-building hermatypic corals. Three species of this genus were previously found only in washings of Acropora and Stylophora in northern...
Ticiane Pokrywiecki Sauer et al.
Journal of hazardous materials, 135(1-3), 274-279 (2006-01-03)
The application of advanced oxidation processes (H(2)O(2)/UV, TiO(2)/H(2)O(2)/UV and TiO(2)/UV) to treat tannery wastewater was investigated. The experiments were performed in batch and continuous UV reactors, using TiO(2) as a catalyst. The effect of the hydrogen peroxide concentration on the...

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