6,8-Difluoro-7-hydroxy-4-methylcoumarin is a fluorophore.¹It has been conjugated to streptavidin or secondary antibodies for flow cytometry and used to label bacteria for multi-color fluorescencein situhybridization (FISH).^2,16,8-Difluoro-7-hydroxy-4-methylcoumarin has also been coupled to peptides to improve electrospray ionization and MS sensitivity in MALDI-TOF MS.³It displays absorption/emission maxima of 358/455 nm, respectively.⁴

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