Horseradish Peroxidase (HRP) is a hemoprotein catalyzing the oxidation by hydrogen peroxide of a number of substrates such as ascorbate, ferrocyanide, cytochrome c and the leuco form of many dyes. HRP has a molecular weight of 40 kDa and an optimum pH of 7.0. Stability: HPOFF is stable for 9-12 months at 2-8