Reactive Oxygen Species Assays
Quantify reactive oxygen and nitrogen species and the enzymes that control them: ROS, hydrogen peroxide, nitric oxide, superoxide and superoxide dismutase activity.
Total ROS by fluorescence, hydrogen peroxide by colorimetric or fluorometric read-out, and nitric oxide.
Superoxide anion production and inhibition, and total, CuZn and Mn superoxide dismutase activity.
Total oxidant status and hydroxyl radical scavenging capacity.
Reactive oxygen species such as superoxide, hydrogen peroxide and the hydroxyl radical are produced by mitochondria and by enzymes such as NADPH oxidase. They act as signalling molecules at low levels and cause damage when they accumulate.
Most ROS are short-lived, so they are measured either with a probe that reacts as they form, through a more stable product such as hydrogen peroxide or nitrite, or through the activity of the enzymes that remove them.
Reactive oxygen species include superoxide, hydrogen peroxide and the hydroxyl radical. Reactive nitrogen species derive from nitric oxide. Both contribute to oxidative and nitrosative stress.
Nitric oxide is unstable, so it is usually measured through its stable breakdown products nitrite and nitrate with a colorimetric reaction.
Superoxide dismutase converts superoxide to hydrogen peroxide. Its activity reports the capacity of the first line of antioxidant defence.