ORANGE Peroxidase Products

Description

The application of antibodies and other proteins covalently coupled to horseradish peroxidase (HRP) in immunohistology is well documented. It is the most frequently used label for immunohistologic techniques. In the presence of peroxide (H2O2), HRP catalyzes the oxidation of phenols, naphthols, diamines, aminophenols, indophenols etc. forming chromogenic products visible by light microscopy. Most commonly employed are 3-amino-9-ethylcarbazole, p-phenylenediamine/catechol, 4-chloro-1-naphthol and diaminobenzidine (DAB). Although a suspected carcinogen, DAB is the most widely accepted donor substrate for peroxidase immunohistochemistry, since it provides a reaction product insoluble in alcohols and xylene. The DAB oxidation product is light brown and may be difficult to visualize if low antigen density occurs. The ORANGE Substrate System is based on oxidative coupling of aromatic amines and phenolic compounds by HRP in the presence of peroxides. Endogenous peroxidase activity is eliminated by controlled oxidation prior to application of antibodies.

Bioinformatics

Alternate Names

DAB