Sigma-Aldrich p-Nitrophenyl Phosphate Liquid Substrate System. alkaline phosphatase substrate, liquid. 100 mL

The p-Nitrophenyl Phosphate (pNPP) Liquid Substrate System combines p-nitrophenyl phosphate, buffer, and the required magnesium cations in a convenient, ready-to-use, single solution reagent. Producing a soluble end product, pNPP is the substrate of choice in alkaline phosphatase enzyme immunoassays.[1]

p-Nitrophenyl Phosphate Liquid Substrate System has been used as a substrate to determine the activity of alkaline phosphatase[2] in alkaline phosphatase assay.[3]

Substrate for alkaline phosphatase that yields a soluble yellow end product that may be read at 405 nm. The reaction may be stopped with 3N NaOH and read at 405 nm. Recommended for ELISA (microwell) procedures, not recommended for membrane applications.

4-Nitrophenyl phosphate disodium salt hexahydrate (pNPP) is a non-proteinaceous and non-specific substrate for determining protein tyrosine phosphatase activity. Hydrolysis of pNPP produces p-nitrophenol.[4] It is a common chromogenic substrate for alkaline phosphatase.[5]

Ready-to-use.

Stable at least one year when stored below 0 °C.