Resorufin is a fluorescent probe and the reduced form of the redox indicator dye resazurin .1 It can be further reduced to hydroresorufin, which is non-fluorescent. Resorufin has been used in the synthesis of resorufin-based fluorescent probes.2,3 It has also been used for the direct measurement of solvent-solute hydrogen bond dynamics with distinct absorption and emission peaks in solvents with strong hydrogen bonds and overlapping peaks in solvents with weak hydrogen bonds.4 It displays excitation/emission maxima of 570/580 nm, respectively.
1.O'Brien, J., Wilson, I., Orton, T., et al.Investigation of the Alamar Blue (resazurin) fluorescent dye for the assessment of mammalian cell cytotoxicityEur. J. Biochem.267(17)5421-5426(2000) 2.Mayer, R.T., Jermyn, J.W., Burke, M.D., et al.Methoxyresorufin as a substrate for the fluorometric assay of insect microsomal O-dealkylasesPestic. Biochem. Physiol.7(4)349-354(1977) 3.Yoon, J.W., Kim, S., Yoon, Y., et al.A resorufin-based fluorescent turn-on probe responsive to nitroreductase activity and its application to bacterial detectionDyes Pigm.171107779(2019) 4.Yu, J., and Berg, M.Resorufin as a probe for the dynamics of solvation by hydrogen bondingChem. Phys. Lett.208(3-4)315-320(1993)