4-Nitrophenyl Phosphate Di(tris) Salt (CAS 68189-42-4), commonly abbreviated as pNPP Di(Tris) Salt, is a widely used chromogenic substrate in biochemistry, molecular biology, and diagnostic research. It is particularly valued for the sensitive detection and quantification of phosphatase enzyme activity, making it an essential reagent in enzyme assays and immunological studies.
Chemical Characteristics
4-Nitrophenyl Phosphate Di(tris) Salt is a stable, water-soluble substrate that undergoes enzymatic hydrolysis in the presence of phosphatases. During this reaction, p-nitrophenol is released, producing a yellow-colored product under alkaline conditions. The intensity of the color can be measured spectrophotometrically, providing a convenient and quantitative method for evaluating enzyme activity.
Its excellent sensitivity, reproducibility, and ease of use have made it one of the most commonly employed phosphatase substrates in research laboratories worldwide.
Applications
Phosphatase Activity Assays
pNPP Di(Tris) Salt is extensively used to measure the activity of acid phosphatases and alkaline phosphatases in biological samples. The colorimetric reaction enables rapid and accurate enzyme quantification.
TRAP Activity Determination
The substrate is widely used to quantify tartrate-resistant acid phosphatase (TRAP) activity in cell lysates. TRAP assays are important in bone metabolism studies, osteoclast research, and related biomedical investigations.
Native PAGE Analysis
Researchers utilize pNPP Di(Tris) Salt to determine phosphatase activity following native polyacrylamide gel electrophoresis (PAGE). This application allows visualization and characterization of active phosphatase enzymes directly within gels.
ELISA and Diagnostic Assays
In enzyme-linked immunosorbent assays (ELISA), pNPP serves as a substrate for alkaline phosphatase-conjugated detection systems. The resulting color development enables sensitive detection of antibodies, antigens, and other biological targets.
Research Advantages
