

TMB Free Base by Molecular Depot is a 3,3′,5,5′-tetramethylbenzidine free base, a colorimetric substrate for detecting horseradish peroxidase labelled probes. Oxidation by the peroxidase gives a blue charge transfer complex read at 650 nm, which turns yellow and is read at 450 nm once acid is added to stop the reaction. It is used as the peroxidase substrate in ELISA and immunoassay detection, in blot staining and in immunoassay development. Each unit contains 5 g. MBP supplies Molecular Depot enzyme reagents to research labs in the United States, Canada and worldwide.