Alkaline phosphatase (AP) is a popular enzyme conjugated with secondary antibody for ELISA. p-Nitrophenyl phosphate (pNPP) is proven to be an effective chromogenic substrate for alkaline phosphates. The SensoLyte® pNPP Alkaline Phosphatase ELISA Assay Kit provides optimized pNPP assay buffer, modified ELISA wash buffer and AP-conjugated secondary antibody. The assay is highly sensitive and has a large dynamic range. The kit contains: • pNPP chromogenic substrate (absorption maximum = 405 nm upon dephosphorylation) • Assay buffer • ELISA wash buffer • Stop solution • Alkaline phosphate-conjugated secondary antibody (goat anti-rabbit IgG) • An optimized ELISA assay protocol.