Diaminobenzidine (3,3'-diaminobenzidine, DAB) is a common chromogenic substrate of horseradish peroxidase (HRP), as an HRP electron donor, loses electrons in the presence of hydrogen peroxide, rapidly changes color, and forms insoluble brown or amber particles through polymerization and other reactions, and settles in situ. This brown precipitate is insoluble in water and ethanol, so after DAB color development, subsequent staining can also be performed using an ethanol-soluble dye.

This kit is a horseradish peroxidase (HRP) substrate detection kit that can be used for immunohistochemistry, in situ hybridisation, protein blotting, spot blotting and other experiments.