A simple, rapid and sensitive staining method for detecting the phosphatase in polyacrylamide gels was developed, in which p-nitrophenyl phosphate (pNPP) was used as substrate.This method was based on the activity of p - nitrophenylphosphatase (pNPPase) to release Pi from pNPP within the polyacrylamide gels which then combines with lead ion to form the lead phosphate and precipitates in the gel as white bands. These bands can be changed to dark brown bands on a transparent background due to formation of PbS by treating with (NH4)2S within the gel.The crude extracts of H22a hepatoma ascites cells and normal mouse liver cells were analyzed by this method and found that there are some difference between the two kinds of cells.
