Reactive oxygen species (ROS) are chemically reactive molecules containing oxygen (such as superoxide, hydroxyl radical, singlet oxygen and peroxides). ROS is highly reactive due to the presence of unpaired valence shell electrons. ROS forms as a natural byproduct of the normal metabolism of oxygen and plays important roles in cell signaling and homeostasis. However, during times of environmental stress (e.g., UV or heat exposure), ROS levels can increase dramatically. It may result in significant damage to cell structures. Cumulatively, this is known as oxidative stress. ROS is also generated by exogenous sources such as ionizing radiation. Under the conditions of oxidative stress, greatly increased production of ROS results in subsequent alteration of membrane lipids, proteins and nucleic acids. Oxidative damage of these biomolecules is associated with aging as well as with a variety of pathological events, including atherosclerosis, carcinogenesis, ischemic reperfusion injury, and neurodegenerative disorders.

ROS Brite™ reagents are a series of new fluorogenic probes to measure oxidative stress in cells. The cell-permeant ROS Brite™ reagents are nonfluorescent and produce bright fluorescence upon ROS oxidation. The resulting fluorescence can be measured using fluorescence imaging, high-content imaging, microplate fluorometry, or flow cytometry. ROS Brite™ 570, 670 and 700 reagents have good selectivity to both hydroxyl radical and supoeroxide.

ROS Brite™ 570 reagent is a new fluorogenic probe to measure oxidative stress in cells using conventional fluorescence microscopy, high-content imaging, microplate fluorometry, or flow cytometry. The cell-permeant ROS Brite™ 570 reagent is nonfluorescent and produces bright orange fluorescence upon ROS oxidation.

ROS Brite™ 670 can be well excited with He-Ne laser at 633 nm, making this reagent well suited for the ROS detection using a flow cytometer. Its fluorescence signal can be well monitored using the Cy5R filter set.

ROS Brite™ 700 reagent is a new fluorogenic probe to measure oxidative stress in small animals. The cell-impermeant ROS Brite™ 700 reagent is water-soluble nonfluorescent and produces bright near-infrared fluorescence upon ROS oxidation. The resulting fluorescence can be measured using in vivo fluorescence imaging.