The fluorescence of NBD is highly dependent on the environment; it is virtually nonfluorescent in water but becomes strongly green fluorescent in hydrophobic media. NBD-ethylenediamine can be readily coupled to activated carboxy groups or sulfonyl chlorides.λEx/λEm (MeOH) = 466/535 nm Yellow solid soluble in DMSO or DMF Store at -20°C and protect from light C8H9N5O3 MW: 223.19