Fast Blue B salt

Fast Blue B is used for the determination of acetylcholinesterase activity. Acetylcholinesterase converts 1-naphthyl acetate to 1-naphthol, which reacts with fast blue B to form a purple-coloured diazonium dye. Similarly, Fast Blue B is also used for α- and β-glucosidase activity.
Fast Blue B has been used in the acid phosphatase test in Clostridium perfringens. It has been used as a spraying agent in thin layer chromatography for the identification of separated components or for the determination of lipase activity.

Synonyme: o-Dianisidine bis(diazotized) zinc double salt; Azoic Diazo No. 48; DBB; Diazo Blue B; Naphthanil Diazo Blue B.