AAT Bioquest offers a selection of substrates and reagents for detecting and measuring phosphatase activity, including tools applicable to protein phosphatases as well as general acid and alkaline phosphatases. Protein phosphatases catalyze the removal of phosphate groups from phosphorylated amino acid residues, playing critical roles in cellular signaling pathways. Our portfolio includes fluorogenic, bioluminescent, and peptide substrates spanning UV to far-red detection wavelengths, enabling researchers to monitor phosphatase activity across diverse experimental platforms including microplate assays, continuous kinetic measurements, and cell-based studies.

Fluorogenic substrates are the most widely used tools for phosphatase detection, producing fluorescent products upon enzymatic cleavage of the phosphate group. AAT Bioquest offers substrates spanning UV-excitable coumarin derivatives to far-red fluorophores, enabling multiplexing and compatibility with various detection instruments.

D-Luciferin phosphate provides ultra-sensitive bioluminescent detection of phosphatase activity. Upon dephosphorylation, the released D-luciferin serves as a substrate for firefly luciferase, generating light that can be detected with exceptional sensitivity. This approach offers the lowest background and highest sensitivity for phosphatase detection.

Phosphorylated peptide substrates provide the most mechanistically relevant tools for studying serine/threonine protein phosphatases such as protein phosphatase 1 (PP1), as they directly mimic physiological phosphoprotein substrates. These peptides contain phosphoserine or phosphothreonine residues that are dephosphorylated by the target enzyme.

For endpoint assays requiring precise timing of phosphatase reactions, Signal Guard™ provides a convenient stopping solution that halts enzymatic activity while stabilizing the fluorescent or colorimetric signal for extended read times.