The β-Galactosidase Enzyme Assay System with Reporter Lysis Buffer is a convenient method for assaying β-galactosidase activity in lysates prepared from cells transfected with β-galactosidase reporter vectors such as the pSV-β-Galactosidase Control Vector.
The standard assay is performed by adding a dilute sample to an equal volume of Assay 2X Buffer that contains the substrate ONPG (o-nitrophenyl-β-d-galactopyranoside). Samples are incubated for at least 30 minutes, during which time the β-Galactosidase hydrolyzes the colorless substrate to o-nitrophenyl, which is yellow. The reaction can be terminated by addition of sodium carbonate, and the absorbance at 420nm is measured by spectrophotometry.
Cat.# E2000 contains sufficient reagents for 65 standard assays or 200 assays in a 96-well plate format.
References
- Miller, J.H., ed. (1972) Experiments in Molecular Genetics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York.
- Sambrook, J. et al. (1989) Molecular Cloning, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York.
- Schenborn, E. and Goiffon, V. (1993) Promega Notes 41, 11–3.