ReadiUse™ Stayright™ Purple is a ready-to-use peroxidase (HRP) substrate designed for chromogenic detection in immunohistochemistry (IHC) and in situ hybridization (ISH) workflows. Traditional 3,3'-diaminobenzidine (DAB) chromogens are widely used for routine IHC because of their sensitivity and low cost, but DAB is associated with mutagenicity and safety concerns for laboratory handling and disposal. Stayright™ Purple was developed by AAT Bioquest as a significantly safer alternative chromogen for HRP-based staining.

The substrate is supplied as a stable premixed solution containing hydrogen peroxide, eliminating the need for separate substrate preparation or mixing before use. In the presence of HRP, Stayright™ Purple undergoes oxidation to form a clean, intense purple insoluble precipitate at the target site. The purple end product is insoluble in organic solvents and organic mounting media, allowing the staining signal to remain compatible with regular dehydration and coverslipping steps. ReadiUse™ Stayright™ Purple is suitable for HRP-based IHC, ISH, and related chromogenic detection applications where a distinct purple signal is desired.