R-phycoerythrin (R-PE) is a naturally fluorescent protein from algae and is composed of a 240KD protein covalently linked to a number of fluorophores called phycobilins. Its exceptional fluorescence characteristics make it a perfect positive control for intracellular protein delivery using OZ Biosciences Pro-DeliverIN reagent (cat. # PI11000). R-phycoerythrin is provided at a 100µg/ml concentration in DPBS pH 7.4. R-Phycoerythrin properties : *Absorption maximum: 498 / 565 nm *Emission maximum: 573 nm *Extinction coefficient: 1.96 x 10^6 M-1 cm-1 *Quantum Yield: 0.84