Dihydroethidium

Dihydroethidium, also known as DHE, is a peroxide indicator. Dihydroethidium penetrates cell membranes to form a fluorescent protein complex with blue fluoresces. After entering the cells, Dihydroethidium is mainly localized in the cell membrane, cytoplasm and nucleus, and the staining effect is the strongest in the nucleus. Dihydroethidium produces inherent blue fluorescence with a maximum excitation wavelength of 370 nm and a maximum emission wavelength of 420 nm; after dehydrogenation, Dihydroethidium combines with RNA or DNA to produce red fluorescence with a maximum excitation wavelength of 300 nm and a maximum emission wavelength of 610 nm. 535 nm can also be used as the excitation wavelength for actual observation[1].

[1]Zielonka J, et al. Global profiling of reactive oxygen and nitrogen species in biological systems: high-throughput real-time analyses. J Biol Chem. 2012 Jan 27;287(5):2984-95.