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 biological system′s detoxification capacity 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 to evaluate the mitochondrial damage by mechanical ventilation (MV). It is also used to measure the production of intracellular ROS._x000D_ Suitability_x000D_ This kit is suitable for the detection of intracellular ROS by fluorescence microplate reader, flow cytometer, or a fluorescent microscope with TRITC filter._x000D_ Principle_x000D_ The Fluorometric Intracellular ROS Assay Kit provides a sensitive, one-step fluorometric assay to detect intracellular ROS (especially superoxide and hydroxyl radical) in live cells within 1 hour incubation. ROS react with a cell-permeable sensor, resulting in a fluorometric product (λex = 540/λem = 570 nm) proportional to the amount of ROS present. The assay can be performed in a convenient 96-well or 384-well microtiter-plate format.