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6,8-Difluoro-7-hydroxy-4-methylcoumarin NHS Ester (FP-1242)



6,8-Difluoro-7-hydroxy-4-methylcoumarin NHS Ester (Marina Blue® NHS Ester) exhibit bright blue fluorescence emission near 460 nm is optimally excited by the intense 365 nm spectra line of the mercury-arc lamp and detect optimally with DAPI optical filter sets. Because the pKa value of 6,8-Difluoro-7-hydroxy-4-methylcoumarin derivatives are 2-3 log units lower compared to those of the corresponding 7-hydroxycoumarin conjugates, 6,8-Difluoro-7-hydroxy-4-methylcoumarin conjugates are strongly fluorescent even at neutral pH.

6,8-Difluoro-7-hydroxy-4-methylcoumarin NHS Ester reacts specifically and efficiently with a primary amine (e.g., side chain of lysine residues or aminosilane-coated surfaces) at pH 7-9 to form a stable, covalent amide bond. The NHS ester (or succinimidyl ester) is the most popular tool for conjugating dyes to the primary amines of protein or antibody (Lys), amine-modified oligonucleotides, and other amine-containing molecules.


Unit Size5 mg, 25 mg, 100 mg
ReactivityPrimary amines
Abs/Em Maxima365/460 nm
Extinction coefficient19,000 cm-1M-1
SolubilityDMSO, DMF
Spectrally similar dyesAlexa Fluor® 350, AMCA, DyLight® 350
Molecular weight367.26
Storage Conditions-20°C.
Shipping ConditionsAmbient temperature

Abs/Em Spectra

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