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Product Line: Pharmaceutical Chemicals

3,3-Diaminobenzidine

CAS 91-95-2

Molecular structure of 3,3-Diaminobenzidine

CAS · 91-95-2

01

Product Overview

3,3-Diaminobenzidine is a high-purity pharmaceutical-intermediates supplied for industrial and specialty chemical applications. Contact our team for specifications, packaging options and lead times.

02

Product Specifications

Appearance: Off-white to brown crystal powder
Purity (HPLC): 97.5% min
Cl: 240 ppm max
Cu: 50 ppm max
Heavy metal: 30 ppm max
03

Applications

 

 

1. Histochemistry and Immunohistochemistry (IHC)

Primary use: DAB is the most widely used chromogenic substrate for peroxidase enzymes (especially horseradish peroxidase, HRP) in IHC staining.

When oxidized by HRP in presence of hydrogen peroxide, DAB forms an insoluble brown precipitate at the site of enzyme activity.

This allows visualization of antigens or proteins in tissue sections under a microscope.

Commonly used in diagnostic pathology to detect cancer markers, infectious agents, and other proteins.

2. Electron Microscopy

Used as a photo-oxidation reagent to localize enzyme activity for ultrastructural studies.

The DAB precipitate is electron-dense, useful for tracing in transmission electron microscopy (TEM).

3. Analytical Chemistry

Acts as a reagent for detecting peroxidase activity in biochemical assays.

Employed in various enzymatic and immunoassay protocols.

4. Chemical Synthesis

Occasionally used as a building block or intermediate in organic synthesis involving aromatic amines.

04

Benefits

 

1. High Sensitivity and Specificity

Produces a strong and stable brown color that is easily visualized.

Provides excellent contrast against tissue background in microscopy.

2. Insoluble and Permanent Staining

DAB reaction product is insoluble in alcohol and organic solvents, making it suitable for permanent slide preparations.

Can withstand multiple rounds of staining or analysis.

3. Compatibility

Compatible with many detection systems and antibody conjugates.

Works well in multiplex staining with other chromogens.

4. Low Background Staining

When used properly, DAB generates low non-specific background, improving clarity and reproducibility.

05

Conclusion

3,3-Diaminobenzidine (DAB, CAS 91-95-2) is a crucial chromogenic substrate widely used in immunohistochemistry and histochemical detection of peroxidase activity. Its ability to form a permanent, electron-dense brown precipitate makes it indispensable in pathology diagnostics, biomedical research, and ultrastructural studies. Proper handling is essential due to its toxic and potentially carcinogenic nature.

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