Fluoride resistant acid phosphatase (FRAP) is a type of acid phosphatase. FRAP is mainly found in
the lysosomes of most cells, the prostate gland, brain, liver, spleen, and platelets.
The activity of fluoride-resistant acid phosphatase is not inhibited by fluoride ions, whereas the
activity of other acid phosphatases is inhibited by fluoride ions. Under acidic conditions, the fluoride-
resistant ion acid phosphatase catalyzes the production of p-nitrophenol from PNPP. The p-nitrophenol
appears yellow under alkaline conditions and can be detected at 400 nm absorbance. The darker the yellow
color of the product, the higher the activity of the fluorine-resistant ion acid phosphatase, and vice versa,
the lower the enzyme activity.
Reagents and Equipment Required but Not Provided:
Spectrophotometer/microplate reader, centrifuge, water bath/incubator, adjustable pipette, Micro glass
cuvettes/96 well plates, mortar/homogenizer/cell sonicator, ice and distilled water