Docosanoyl Ethanolamide is a fluorescent probes for ROS detection. Most fluorescent probes, such as 2,7-dichlorofluorescein (DCFH), function by an oxidative mechanism and are useful for total oxidant detection but are not selective for hydrogen peroxide specifically.Docosanoyl ethanolamide functions by a nonoxidative mechanism, where it fluoresces upon perhydrolysis of the sulfonyl linkage, and is selective for hydrogen peroxide over hydroxyl radical, tert-butyl hydroperoxide, nitrates, singlet oxygen and superoxide anion. Pentafluorobenzenesulfonyl fluorescein can be used as a probe for hydrogen peroxide in whole cell systems.