Alkaline Phosphatase in Leucocytes by An Azo Dye Method

Abstract
Alkaline phosphatase activity was demonstrated in the cytoplasm of leucocytes of man, rat and rabbit by means of naphthol AS phosphate as the substrate and fast blue BBN as the coupling agent. The reaction was effected in Tris buffer, 0.2 M at ph 9.1, in 5-10 min at 25°C. Air-dried smears, with or without fixation in 10% neutral formalin, showed activity but those heated 1 min in water at 100°C did not.