4-Nitrophenyl b-D-arabinopyranoside

4-Nitrophenyl b-D-arabinopyranoside is a fluorogenic substrate that is used in food testing to measure the activity of β-galactosidase. It can be used as a chromogenic substrate for the detection of β-lactamase and β-glucuronidase enzymes. 4-Nitrophenyl b-D-arabinopyranoside is also used as a ligand to detect alkaline phosphatase activity, and as an enzyme substrate in diagnostics.