6,8-Difluoro-7-hydroxy-4-methylcoumarin is a fluorophore.1 It has been conjugated to streptavidin or secondary antibodies for flow cytometry and used to label bacteria for multi-color fluorescence in situ hybridization (FISH).2,1 6,8-Difluoro-7-hydroxy-4-methylcoumarin has also been coupled to peptides to improve electrospray ionization and MS sensitivity in MALDI-TOF MS.3 It displays absorption/emission maxima of 358/455 nm, respectively.4
1.Takada, T., Matsumoto, K., and Nomoto, K.Development of multi-color FISH method for analysis of seven Bifidobacterium species in human fecesJ. Microbiol. Methods58(3)413-421(2004) 2.Telford, W.G.Analysis of UV-excited fluorochromes by flow cytometry using near-ultraviolet laser diodesCytometry A.61(1)9-17(2004) 3.Pashkova, A., Moskovets, E., and Karger, B.L.Coumarin tags for improved analysis of peptides by MALDI-TOF MS and MS/MS. 1. Enhancement in MALDI MS signal intensitiesAnal. Chem.76(15)4550-4557(2004) 4.Sun, W.C., Gee, K.R., and Haugland, R.P.Synthesis of novel fluorinated coumarins: Excellent UV-light excitable fluorescent dyesBioorg. Med. Chem. Lett.8(22)3107-3110(1998)