Search
Search

| Catalog Number | Quantity |
|---|---|
| E6646 | 100 Assays |
See our complete line of Fluorescence Microplate assays.
In the presence of inorganic phosphate, the 2-amino-6-mercapto-7-methylpurine riboside (MESG) substrate is converted by the purine nucleoside phosphorylase (PNP) enzyme to the ribose 1-phosphate and 2-amino-6-mercapto-7-methylpurine product. This enzymatic conversion of MESG results in a spectrophotometric shift in maximum absorbance from 330 nm for the substrate to 360 nm for the product.
Sensitivity of the assay is in the range of 2 to 150 μM inorganic phosphate (2 to 150 nanomoles phosphate in a 1 mL volume), and the reaction can be performed over a pH range of 6.5 to 8.5. The EnzChek™ phosphate reaction is sufficiently fast and quantitative for use in stopped-flow kinetic experiments.