Nitrotetrazolium Blue (NBT) is used in combination with 5-bromo-4-chloro-3-indoxyl phosphate (BCIP) to detect alkaline phosphatase activity in blotting techniques and in situ hybridization chemistry. BCIP acts as the substrate for alkaline phosphatase, and the oxidizing reagent NBT enhances the purple-brown final color of the precipitates at the reaction sites.

NBT has also been used with X-Gal,or Salmon-Gal to speed up and enhance colony screening.

NBT Reduction Test: Assessment of reduction of NBT dye by stimulated and unstimulated neutrophils.

Product Specifications
Nitrotetrazolium blue chloride, NBT;
Nitro blue tetrazolium chloride;


Formula: C40H30N10O6Cl2

MW: 817.65 g/mol

Storage/Handling: Store at 4°C. Protect from light.

PubChem Chemical ID: 9281