Not available outside of the UK & Ireland.

General description

Red fluorophore standard. Widely used in enzyme assay systems. Absorption and fluorescence of resorufin are pH dependent. Below the pKa (~6.0), Abs. shifts to ~ 480 nm and both E and fluorescence quantum yield are markedly lower. Resorufin is unstable in the presence of thiols such as dithiothreitol (DTT) and 2-mercaptoethanol.

Resorufin has high extinction coefficient and good chemical and photostability. These properties of resorufin make it perfect for its usage in inverse fluorescence assay to detect H₂O₂ by measuring the disappearance of its fluorescence upon horseradish peroxidase-mediated oxidation to a nonfluorescent derivative.