R-Phycoerythrin (RPE+) is a phycobiliprotein isolated from a species of red algae chosen specifically because it yields one of the most highly fluorescent of the RPEs. Like other phycobiliproteins, RPE+ is fluorescent, with an extremely high absorptivity,

May be used in the biotinylation of proteins and peptides. Typically coupled to primary amine in the pH range 6.5-8.5.

Biotinylation reagent incorporating an extended 14-atom spacer can$nreduce steric hindrance in binding avidin or streptavidin to some$nbiotinylated compounds and increase sensitivity for detection. Typically$ncoupled to primary amine in the pH range 6.5-8.5.