FAM NHS ester, 6-isomer – CAS 92557-81-8


FAM NHS ester, 6-isomer – CAS 92557-81-8 is provided by Santiago Lab (Prague, Czech Republic)

Purity (LC-MS)

min 95%

Package contents

FAM NHS ester, 6-isomer

This compound is for research use only. We do not sell to patients.
100 mg

In stock

1 g

In stock


FAM NHS ester, 6-isomer – CAS 92557-81-8


CAS: 92557-81-8

IUPAC Name: (2,5-dioxopyrrolidin-1-yl) 3′,6′-dihydroxy-1-oxospiro[2-benzofuran-3,9′-xanthene]-5-carboxylate

Other names: 6-Carboxyfluorescein N-succinimidyl ester, FAM NHS ester, 6-isomer, 6-FAM SE, 6-Carboxyfluorescein-NHS

Molecular weight: 473.4 g/mol

Molecular formula: C25H15NO9

InChI: InChI=1S/C25H15NO9/c27-13-2-5-16-19(10-13)33-20-11-14(28)3-6-17(20)25(16)18-9-12(1-4-15(18)24(32)34-25)23(31)35-26-21(29)7-8-22(26)30/h1-6,9-11,27-28H,7-8H2

Solubility: DMF, DMSO

Excitation/absorption maximum: 492 nm

Emission maximum: 517 nm


Explore the brilliance of Fluorescein (FAM), a vibrant fluorophore widely embraced in life science research for its versatility. Known for its hydrophilic nature, fluorescein derivatives exhibit excellent solubility in aqueous buffers.

With broad compatibility, fluorescein seamlessly integrates with a diverse range of fluorescent instrumentation, as most devices come equipped with FAM channel filters. This ensures convenient and efficient use across various research applications.

Our product proudly features the pure 6-isomer of fluorescein, ensuring the highest quality for your experiments. Immerse yourself in the world of fluorescence with the exceptional properties of Fluorescein, unlocking new possibilities in your life science endeavors.


  • Saito K, Komamine A. Biosynthesis of stizolobinic acid and stizolobic acid in higher plants. An enzyme system(s) catalyzing the conversion of dihydroxyphenylalanine into stizolobinic acid and stizolobic acid from etiolated seedlings of Stizolobium hassjoo. Eur J Biochem. 1976;68(1):237-243. doi:10.1111/j.1432-1033.1976.tb10783.x


You can find more fluorescent labels in our catalog: https://www.santiago-lab.com/cat/labels/

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