Thermo Scientific™ DyLight™ 550 Maleimide

The Thermo Scientific™ DyLight™ Dyes have absorption spectra ranging from 350 to 770nm. These reagents fluoresce over a broad pH range, are more intense than Alexa Fluor™ or Cy™ Dyes in many applications and match the output wavelengths of common fluorescence instrumentation. Additionally, the water solubility of the DyLight Reagents allows a high fluor-to-protein ratio without precipitation during conjugation.
The sulfhydryl-reactive dyes contain maleimide groups that react predominantly with free –SH groups at pH 6.5-7.5, forming a stable thioether bond. At pH 7, the maleimide group is ∼1000 times more reactive toward a free sulfhydryl than to an amine.1At pH values > 7.5, reactivity toward primary amines increases and hydrolysis of the maleimide group can occur.

Highlights:

• Specific — maleimide-activated dye labels proteins and other molecules at reduced sulfhydryls (-SH)
• Efficient labeling methods — well-characterized chemistry and optimized protocols provide for reliable, high-quality labeling
• Optimized antibody labeling procedure —complete protocol for IgG reduction and labeling and calculating the labeling efficiency

Applications:

• Antibody labeling for immunofluorescence applications, including immunocytochemistry (ICC), immunohistochemistry (IHC), Western blotting and ELISA assay
• Target macromolecule labeling for in vitro and in vivo fluorescent detection strategies