5(6)-Carboxyfluorescein N-hydroxysuccinimide ester (5/6-FAM SE) ≥90% (by HPLC) fluorescent dye, Pierce™

Supplier: Thermo Fisher Scientific

Synonyms: NHS-Fluorescein, FLUOS, 5(6)-FAM SE

46410 46409
PIER46410EA 114 GBP
PIER46410 PIER46409
5(6)-Carboxyfluorescein N-hydroxysuccinimide ester (5/6-FAM SE) ≥90% (by HPLC) fluorescent dye, Pierce™
5(6)-Carboxyfluorescein N-hydroxysuccinimide ester (5/6-FAM SE)

NHS fluorescein [(5/6-carboxyfluorescein succinimidyl ester), mixed isomer] is an amine reactive derivative of fluorescein dye for antibodies and other probes in fluorescence microscopy, flow cytometry, and immunofluorescence based assays such as western blotting and ELISA.


  • Label antibodies for use as immunofluorescent probes
  • Label oligonucleotides for hybridization probes
  • Detect proteins in gels and on Western blots
  • Excitation⁄Emission - 494⁄518 (nm)


NHS fluorescein is activated with the N-hydroxy-succinimidyl (NHS) ester functional group. These fluorescein dyes are mixtures of isomers with reactive groups attached at the fifth and sixth positions of the bottom ring. The properties of these isomers are indistinguishable in terms of excitation and emission spectra and for protein applications there is no need to isolate a specific isomer.

Formula: C₂₅H₁₅NO₉
MW: 473,39 g/mol
MDL Number: MFCD04119713
CAS Number: 117548-22-8

Order Now

Learn more

About VWR

Avantor is a vertically integrated, global supplier of discovery-to-delivery solutions for...

Learn more About VWR