Detecting alkaline phosphatase–labeled cells

Abstract

Different substrates are available for detection of cells labeled with alkaline phosphatase. Naphthol-AS-BI-phosphate (NABP)/New Fuchsin produces an intense red product that is insoluble in alcohols as well as aqueous solutions and is compatible with a range of histochemical stains. Bromochloroindoyl phosphate/nitro blue tetrazolium (BCIP/NBT) is the most commonly used of the chromogenic substrates for alkaline phosphatase. It is somewhat more sensitive than NABP/New Fuchsin but gives less contrast during microscopic observation.