p-Nitrophenylphosphate Substrate, Alkaline Phosphatase (AP), (pNPP)


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SKU Unit Size Price
SK-5900-18 18 ml

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p-Nitrophenylphosphate AP Substrate is ideal for ELISA using alkaline phosphatase enzyme detection systems. The reagent is supplied in a stabilized concentrate. The bright yellow color of the soluble reaction product is measured at 405-420 nm, providing an excellent reagent for microtitration plate readers.


  • Consistent and reliable
  • Produces 360 ml of working solution


More Information
Unit Size 18 ml
Applications ELISAs
Recommended Storage 2-8 °C, for long term storage -20 °C.
Recommended Usage Recommended dilution for enzyme immunoassays:add five drops (100 µl) of pNPP concentrate per 2 ml of 100 mM sodium bicarbonate/carbonate buffer,* pH 10.0. Optical density readings can be made using wavelengths between 405 nm and 420 nm. *To a 100 mM sodium bicarbonate solution (0.84 g/100 ml water) add either solid sodium carbonate or concentrated sodium hydroxide until solution is pH 10.0.
Concentration 100 mM
Detection Enzyme(s) Alkaline Phosphatase
Substrate Reaction Product Soluble Reaction Product
Chromogen Color Yellow