H2DCFDA (DCFH-DA) is a cell-permeable probe used to detect intracellular reactive oxygen species (ROS) production. It is de-esterified intracellularly and turns to highly fluorescent 2′,7′-dichlorofluorescein upon oxidation. It is used in sensitive and rapid quantitation of oxygen-reactive species in response to oxidative metabolism; microplate assay for detecting oxidative products in phagocytic cells, and quantitative multiwell myeloid differentiation assay.(Ex/Em=488/525 nm)