Description_x000D_ General description_x000D_ Reactive oxygen species (ROS) are generated as a result of the reduction of oxygen during aerobic respiration and by various enzymatic systems within the cell. At physiological levels, ROS contribute to cell signaling and host defense. Increased ROS generation, above the detoxification capacity of the biological system, results in oxidative stress and cellular damage. The main damage to cells results from the ROS-induced alteration of macromolecules such as polyunsaturated fatty acids in membrane lipids, essential proteins, and DNA. ROS has been implicated in disease states, such as Alzheimer′s disease, Parkinson′s disease, cancer, and aging._x000D_ Application_x000D_ Fluorometric intracellular reactive oxygen species (ROS) Kit has been used for detection of intracellular ROS in live cells._x000D_ Suitability_x000D_ This kit is suitable for the detection of intracellular ROS by fluorescence microplate reader or a fluorescent microscope._x000D_ Principle_x000D_ The kit provides a sensitive, one-step fluorometric assay to detect intracellular ROS (especially superoxide and hydroxyl radicals) in live cells within 1 hour incubation. ROS react with a cell-permeable sensor, resulting in a fluorometric product (λex = 520/λem = 605 nm) proportional to the amount of ROS present The assay can be performed in either a 96 or 384 multiwell plate format using a fluorescence microplate reader.