DHR is a cell-permeable fluorogenic probe that is used as an indicator of intracellular peroxynitrite formation. It is oxidized by peroxynitrite to the highly fluorescent product rhodamine in vitro. Neither nitric oxide, superoxide, nor hydrogen peroxide alone appear to oxidize DHR. Formation of rhodamine can be monitored by fluorescence spectroscopy using excitation and emission wavelengths of 500 and 536 nm, respectively, or by absorbance spectroscopy at 500 nm (ε = 78,800 M−1cm−1). DHR has been used to investigate reactive oxygen intermediates produced by endothelial cells, eosinophils, and reactive microglia.
Dihydrorhodamine 123 (DHR) has been used for the detection of free intracellular radicals or ROS (reactive oxygen species) in head kidney-derived macrophages. It has also been used in DHR assay in red blood cells and in oxidative burst assay in neutrophils.
Dihydrorhodamine 123 is the uncharged and nonfluorescent reduction product of the mitochondrion-selective dye rhodamine 123 used for investigation of reacitve oxygen intermediates.
Cell-permeable fluorogenic probe that is useful for the detection of reactive oxygen species (ROS) such as peroxide and peroxynitrite. Dihydrorhodamine is not fluorescent unless it is converted to rhodamine 123.