Dihydrorhodamin 123 - DHR

Dihydrorhodamine 123 is a cell-permeable non-fluorescent substance used as an indicator for reactive oxygen species (ROS) substances. Dihydrorhodamine 123 will diffuse across membranes where it is oxidized by peroxynitrite to rhodamine 123 which localizes in the mitochondria and exhibits green fluorescence (Ex/Em wavelengths of 500 and 536 nm).

Dihydrorhodamine 123 is used for investigation on reactive oxygen intermediates produced by human and murine phagocytes, activated rat mast cells and cultured endothelial cells. In addition, it has been used together with Fura Red calcium indicator to simultaneously measure oxidative bursts and Ca2+ fluxes in monocytes and granulocytes. Dihydrorhodamine 123 has been shown to be a more sensitive probe than H2DCFDA for detecting granulocyte respiratory bursts.